I have 4 remarks to the points given by some people on price/costs of bi-amped or tri-amped systems, that they are too costly and will remain in a niche.

1) this is the 20K and up forum, prices for better performance do not matter.

2) if you still beleave that there is such a huge sonic difference between MOSFET amps, that you need the most expensive one 3 times, for a tri-amped speaker, you are ready for that next a/b level matched blind folded amp test. Things will change for you guaranteed, if the passive speaker's impedance is well constucted (not that 2 Ohm BS some cherish).

3) it should be clear by now that the controll of the drivers achieved with a tri-amped design, even with lesser value amps outperforms a good high end amp running through an art-looking passive x-over.

4) However, some people are not ready to be de-coupled from the passive x-over "MATRIX" :D

Yes, but do you listen to a violin with it 2' from your face or is it at least 10' away? You don't want to digitally remove a distance and room acoustic effect that we are used to hearing and generally like.

While I will agree with you on active x-overs and bi- and tri-amping as superior speaker concepts, I do not see what that remark has to with the space in the recording ? Getting a grip on room accoustics and power response will simply focus the phantom image between any two speakers. It will not make the violine nearer, just smaller and more focused, with more detail of resonance timbre of the instrument and the reverb/space it is recorded in. If the violine was recorded in a huge full of reverb room 10 meters away from the microphone, it will still be the case.

Whenever you bring this up (and I'm not doubting the fact of ringing with too steep a digital slope, it has been reported in many places) you seem to use it as a criticism of the deqx. As the deqx can do as small as 6db slopes (and they themselves caution against steep slopes), I'm a little confused about the absolute importance of the point.

Greg thinks DEQX is a 'mid-fi POS' to use his words and that TacT is the holy grail, even though DEQX is much more advanced in its capabilities. So he uses this as a straw man argument while ignoring that fact that pretty much all filters ring.

the point I tried to make earlier with dave wilson. I bet he does some experimentation too.

Sometimes he even goes to see a concert and realizes his speakers don't sound like live music ;)

Re this ringing everyone talks about, I mean if I ask 'what is this digital ringing', does that mean I am not getting it? Not sure how to phrase it, but is it so obvious that 'you will know it when you have it' type thing?

In hundreds, maybe thousands of hours of listening to the DEQX unit, I've never heard anything like 'ringing' as an artifact, though *maybe* if you could take it away and put it back in, I might be able to hear it. Hard to say because the *overall* result is a huge leap ahead of most anything I've heard


We just did a little blind test on the w/end, whereby we had a twenty thousand dollar front end combo (cdp, 'good' interconnects and cables, class A mono blocks etc) vs a twenty year old denon cdp and amp, house electrical wiring for speaker cables and those crappy little interconnects for hooking it up.

We did it blind (hung a blanket to hide the view) and level matched.

the difference?? To me, totally inconsequential. (to be true, most picked the better as being preferrable, but all agreed that they were surprised at how close it was)

We did a similar thing once, with different speakers to test whether the best easily available electronics and ancillaries (over $20K) could make a $5000/pr speaker better than an overall better $6K/pr speaker. It didn't. Not even when we 'crippled' the better speaker with a Fisher CD player and out of the box, 20 year old patch cables and a zip cord.

Is worrying about ringing also falling into the negligible category? (esp if we 'ignore' the good digital x-overs and dsp can bring)

I suspect it is because I sure couldn't hear it as a distortion and NHT apparently felt that the 110dB/octave crossover (and Legend at ~96dB/octave) did more to improve the sound than deteriorate it. It certainly is less audible than the sound of a D'Appolito driver array and the sound of a port going. Definitely less audible than the sound of a passive crossover.

We did a similar thing once, with different speakers to test whether the best easily available electronics and ancillaries (over $20K) could make a $5000/pr speaker better than an overall better $6K/pr speaker. It didn't. Nothing like comparing apples and oranges for insight.

That is one of the most maddening aspects of your attitude.. That puerile refusal to concede .. regardless of the argument's value .

Why would I concede to BS?!?

Where is the BS? His statement is factual not an opinion.. ]Yours however is a trivialization.. . What is wrong with conceding, learn and move on?

It may be a fact for a set of math equations, but building a speaker is not a math equation. It is a set of real world problem that have to be addressed simultaneously. The result in EVERY case is a compromise. A huge compromise. A Wilson X2 is compromised. A Magico V5 is compromised. A Rockport Arrakis is compromised. By necessity. Using DSP helps reduce the need for compromise by taking some of the problems out of the 'equation' and lets them be dealt with in other manners, primarily time and FR. The amount of compromise necessary to have good temporal response is staggering in the passive world. Not with DSP.

His points do help understand why correcting at all costs toward obtaining a flat FR is NOT the right path.. it does not mean however that all systems with flat FR presents temporal problems. It points toward something most of us understand intuitively: The less correction needed, the better the results.. IOW if you start with a good speaker in a well-treated room the less correction you need to apply and better your results shall be.
Just throwing digital DSP or anything at less than optimal drivers or cabinets or designs is not going to make a great speaker, Digital Active Crossovers are NOT a sufficient condition for a great speaker... Digital Crossovers are not a panacea.. To use your terms there is no silver bullet in real life.

Once again, Frantz, you are putting words in my mouth. Let's put it this way. You're a general in a war. You have multiple battlefields, limited resources and a result that is in question. Suddenly, the Air Force shows up with F22s and Global Hawks and says 'hey, we can take a few of these battlefields off your hands and you can concentrate on the remaining ones'. The result means assured victory and fewer casualties. Do you say 'nah, i don't like that idea, it's not a perfect'?

Nothing like comparing apples and oranges for insight.

Actually, it does provide insight. For years, many reviewers and audiophiles claimed (and still do) that the ancillaries are not only critical, they even outweigh the sound of the speaker. That was easily proven untrue. Speakers still are the biggest source of distortion, aside from a particularly bad room.

If you just crank the "FR flatness" knob up to "11" and think you are doing the best
processing and getting the best sound - then that is just indicative of audio naivete.

No one has proposed this.

It may be a fact for a set of math equations, but building a speaker is not a math equation. It is a set of real world problem that have to be addressed simultaneously.
That is silly talk. Believe it or not, some math equations have more than one variable; but maybe you didn't get that far in math. What tool do you think speaker designers use to solve those multiple "real world" problems? What is a crossover slope but a math equation. What is a speaker resonance but a math equation. What is ringing but a math equation. Speaker design is nothing but a complex math equation. And in particular, DSP is nothing but a complex math equation.

Greg thinks DEQX is a 'mid-fi POS' to use his words and that TacT is the holy grail, even though DEQX is much more advanced in its capabilities. So he uses this as a straw man argument while ignoring that fact that pretty much all filters ring.
John,

BALONEY!!!

First - not all filters ring. You can design filters that don't ring. It all has to do with the roots
or eigenvalues of the characteristic equation. If you have complex roots - that is roots which
have imaginary components [ a component proportional to the square root of -1 ]; then you
get ringing. If you have all real roots - you don't get ringing. Additionally, it is the acausal
"pre-ringing" - that is the filter starts sounding before it should - that is the most objectionable.
Look at Keith Howard's #3 "Minimum Phase Filter"; which doesn't "pre-ring" in response to
an impulse:

http://www.stereophile.com/reference/106ringing/index1.html

Secondly - I don't think DEQX is a "mid-fi POS". I think that someone can take
a DEQX and incorporate it into their product; and with poor choice of filter parameters;
can easily wind up with a "mid-fi POS".

However, the DEQX, in and of itself; is NOT a "mid-fi POS" - it all depends on how it
is used and / or abused.

I would disagree that the DEQX is more advanced in its capabilities than the TacT - and
in fact I would say it is the other way around. I did a lot of research when I was looking
at incorporating either a DEQX or TacT into my system and considered BOTH of them.
In fact, the DEQX had an advantage in that it had 3 channels to the TacT's 2 channels;
which would fit the application better. Alas, I concluded that the TacT unit was MUCH
more advanced than the DEQX - and I know the math - you don't.

2) if you still beleave that there is such a huge sonic difference between MOSFET amps, that you need the most expensive one 3 times, for a tri-amped speaker, you are ready for that next a/b level matched blind folded amp test. Things will change for you guaranteed, if the passive speaker's impedance is well constucted (not that 2 Ohm BS some cherish).

It amazes me that people will spend $20K on a stereo amplifier, but wouldn't spend even $1500 on a 6-channel amplifier that would blow the big amp out of the water. Getting a huge expensive amplifier is like putting a turbo on your engine because your 2-wheel drive car keeps getting stuck in the mud, rather than getting 4-wheel drive.

While I will agree with you on active x-overs and bi- and tri-amping as superior speaker concepts, I do not see what that remark has to with the space in the recording ? Getting a grip on room accoustics and power response will simply focus the phantom image between any two speakers. It will not make the violine nearer, just smaller and more focused, with more detail of resonance timbre of the instrument and the reverb/space it is recorded in. If the violine was recorded in a huge full of reverb room 10 meters away from the microphone, it will still be the case.

I am saying there is a loss of high frequencies and an increase in low frequencies that we are used to hearing and if you take this away by making it perfectly flat at the listening position, it is likely to sound bright and harsh. Athena Project. Keep in mind, recordings aren't mixed outside!

BALONEY!!!

That's what I say!

First - not all filters ring. You can design filters that don't ring. It all has to do with the roots
or eigenvalues of the characteristic equation. If you have complex roots - that is roots which
have imaginary components [ a component proportional to the square root of -1 ]; then you
get ringing. If you have all real roots - you don't get ringing.

And who has this?

Secondly - I don't think DEQX is a "mid-fi POS". I think that someone that someone can take
a DEQX and incorporate it into their product; and with poor choice of filter parameters;
can easily wind up with a "mid-fi POS".


John,

Quit shilling for that miserable "mid-fi" crap from DEQX.

Text edited to remove personal insults

I would disagree that the DEQX is more advanced in its capabilities than the TacT - and
in fact I would say it is the other way around. Alas, I concluded that the TacT unit was MUCH
more advanced than the DEQX - and I know the math - you don't.

In what ways?

A while back I posted my experience with Meridian speakers as compared to the Revels with good electronics connected to both..Oddly it was deleted...I was curious as to what you feel sounds better. You seem to adore the Revels (like myself) , but you also like the Meridians...I don't. They are much less enjoyable to me.

Whats a better speaker?

Thanks Joey

That is silly talk. Believe it or not, some math equations have more than one variable; but maybe you didn't get that far in math.

Actually, I did very well in all my college math courses. Math is pretty easy, just kind boring and leads to the inability to communicate effectively with others.

What tool do you think speaker designers use to solve those multiple "real world" problems? What is a crossover slope but a math equation. What is a speaker resonance but a math equation. What is ringing but a math equation. Speaker design is nothing but a complex math equation. And in particular, DSP is nothing but a complex math equation.

You have one very advance 'math equation' and a bunch of real problems. The addition of the math makes the solution to the other acoustic problems easier and with far more options.

In what ways?
John,

Mathematically, the TacT filters are better. Additionally, TacT had the DRC - dynamic
room correction - capability that they pioneered. DEQX didn't have anything like it at
the time - in fact nobody did. Kal Rubinson added that Audyssey now has DRC.
It appears that DEQX has yet to master the technique of DRC.

You have one very advance 'math equation' and a bunch of real problems. The addition of the math makes the solution to the other acoustic problems easier and with far more options.
Those so-called real world problems are math equations; you solve them with math equations; the resulting solution is a math equation. It is categorically wrong to say:
building a speaker is not a math equation.

Actually, I did very well in all my college math courses. Math is pretty easy, just kind boring and leads to the inability to communicate effectively with others.
John,

When we were discussing the Maxx-2; you didn't even know you had to keep UNITS
consistent. You gave an equation for force that ended up with the force having units
of kg per meter. You said the force exerted on the cabinet by the speaker was the
product of the mass of the driver and excursion divided by the area of the driver.

I would expect a grade schooler to do better than that.

Besides; John; do you mean to tell me that you know Fourier Transforms - which is
the mathematics needed here?

Alimentall and Andreas,

If you go back to my original post:

If you take a person who might have bought a 500wpc amp for a pair of 3-way passive speakers and instead use active crossovers, he might then instead go with 3 amps, perhaps 400wpc, 250wpc, and 100wpc...the total cost will still be much greater than the single 500wpc amp of equivalent quality. [emphasis added]

I am not talking about comparing 1 expensive amp to 3 cheap ones. I'm talking about the cost of 3 amps vs 1 of of equivalent quality. That might mean cheap Behringer or equivalent stuff or it might mean pricey Bryston or it mean even more pricey ML or Lamm or whatever...whatever the user wants.

If you look at the history of active speakers, the burden is on you guys to prove that they'll break out of their niche status. Has Meridian taken over the world? Linn Activ? JL Audio Primacy? (It seems that NO ONE has even reviewed the JL X3, which should be a hint of something.) How many pairs of NHT Xd were sold, despite generally glowing reviews? 200? Before NHT discontinued them. Like Paradigm discontinued their Reference Active series years ago. (I own a pair of Active/40s.)

Yes, DSP adds a new "twist" to things and may improve the odds, but then again, Meridian hasn't taken over the world, and the NHT Xd FAILED in the market.

Those so-called real world problems are math equations; you solve them with math equations; the resulting solution is a math equation. It is categorically wrong to say:

I agree ... Not THINKING of it as such does not change what it is intrinsically.. A set of math equations.. The thing has aq physical existence, thus it can be modelized and indeed that is how one build a speaker these days, ANY speaker, through modelization...

And who has this?

John,

Who has filters that don't ring? Meitner / EMMLabs for one.

The Meitner DACs, for example; use a filter that is wide band and optimally flat in
frequency response. However, the DAC monitors the input signal, and when it detects
a large transient that might trigger ringing - the Meitner DAC switches to a filter
that has better temporal accuracy and doesn't ring.

I agree ... Not THINKING of it as such does not change what it is intrinsically.. A set of math equations.. The thing has aq physical existence, thus it can be modelized and indeed that is how one build a speaker these days, ANY speaker, through modelization...
Frantz,

EXACTLY!!! The speaker obeys the Laws of Physics; and ALL the Laws of Physics
are cast as equations.

I'm a computational physicist - I simulate devices that are MUCH more complex than
a speaker - and we do that with mathematics, equations, and computer programs that
are based on those equations.

I have not read every post on this thread but I did spend ten years selling digital room correction products. In my humble opinion, the reason digitally active speakers (or more generically, digital speaker solutions) will not succeed in in a large way in high end audio are as follows (actually, they may ultimately be more successful in the mid-fi market!):

1. While time may change this, there has yet to be a digital solution to speakers that can work (effectively and correctly) without any serious human intervention. The Audessy automatic solution is awful. I own a Tact and to get any kind of seriously good results requires lots of human intervention. And that is the problem. Problem (1) If I'm a dealer and can either sell a pair of $x,000 speakers cables (or amp, or preamp or ...)by loaning them to the customer and see if he likes them OR go to his home (assuming I am even reasonably competently trained to do so) spend hours and hours and hours setting up his deQX, Tact or ...) which do you think I will do? I can tell you from experience what they will do. (2) And if the mass of dealers (with the high turnover rate in a typical dealer) has no real clue how to diddle with active solutions (yes, I know there are some dealers who are competent and can learn this stuff but most aren't and with employee turnover, that can change as well), how well do you think the typical audiophile will do? There are some (many? most?) who post on this thread who are evidently capable but again, from very personal experience, the typical guy (and where the necessary volume/revenue must come from) who has a $20,000 system at home (or $60,000 or $260,000) is clueless...and more importantly, has no interest in becoming knowledgeable on this subject. He just wants to have great sound (or maybe just impressive looking equipment to impress his friends) and must depend on the dealer to make it work.

2. Remember tone controls?

3. And if lack of competence on the dealers staff isn't enough, you still have the issue of reducing the option to sell more expensive boxes to the customer if you sell him a digitally active speaker that includes all of the boxes.

Having heard systems with active digital crossovers and systems that use digital room correction, (and many more that use neither) there is not a shred of doubt in my mind which approach provides the more accurate/enjoyable/involving solution. But I think we have a long way to go before any of these approaches gains traction in the high end audio community.

1. While time may change this, there has yet to be a digital solution to speakers that can work (effectively and correctly) without any serious human intervention. The Audessy automatic solution is awful. I own a Tact and to get any kind of seriously good results requires lots of human intervention. And that is the problem.
audioguy,

I would agree with that. As a TacT owner; it is not a "plug and play" device. One needs
to spend the requisite time tweeking the "target curves" and crossover settings. If you
have the patience and the technical accumen to do this - then the TacT offers you all
the knobs and tools you need to optimize the performance.

Again, as always in the audio world; there's no free lunch. "You pays your money and
you takes your chances."

Lyngdorf, DEQX, and Audyssey are attempting to be more "plug and play"; they do the
tweeking. You describe how successful they are at doing this.

Again, as always in the audio world; there's no free lunch. "You pays your money, and
you takes your chances."

There is NO DOUBT that speakers are the weakest link of the Reproduction chain.. What we should refrain from are difficult to verify statements those that are based on a belief rather than tests.. Example : 3 cheap amplifiers will be better than one expensive one.. Have any of those advancing this have actually performed this experiment? And are able to conclude with certainty that it is so? Or is just well a belief and opinion, an "audiophile" hyperbole? There are various ways to make a system better and they all do not involve replacing your speakers so yes, Speakers are a factor not the only..

This was being written before Audioguy post... I beleive one of the current problem with the approachis the great difficultyto really obtain results... It requires, so far, I have only heard a few TaCT-based systed and only ONE DEQX s.. They sounded good in both instance but so far the best systems I have heard have been passive and none had active crossovers. It does not mean that I can infer that the best systems must use a passive approach.. simply that at this stage of the game although I BELIEVE that Active Digital Crossovers should present better results, the best systems, me, myself and I have heard have beem simple audiophile orthodox, less is more systems... Source--->Preamp----> amps--->speaker...

JL Audio Primacy? (It seems that NO ONE has even reviewed the JL X3, which should be a hint of something.)

The JL has not been released yet.

Morbius,

I have great respect for your knowledge and enjoy reading your posts, but to suggest that great knowledge cannot come from sources outside of education and accepted science is just short sighted! :p :) :D

http://www.ohgizmo.com/wp-content/uploads/2008/03/monolith.jpg

The JL has not been released yet.

Thanks for the info, Tim. Though judging from the Primacy X3 thread, there may not be very many people waiting with baited breath for it.

Morbius,
I have great respect for your knowledge and enjoy reading your posts, but to suggest that great knowledge cannot come from sources outside of education and accepted science is just short sighted!

I don't know about "great knowledge"; but anything that will make our audio reproduction
system sound better will be grounded in science.

The devices that we use for audio playback obey the Laws of Physics; and the encoding
and processing done in digital audio obey certain laws of Mathematics.

We can't pretend that these devices are doing something "magical" that is outside the
realm of science and mathematics.

How you judge the results and how the music makes you "feel" and what your music
and audio preferences are; are definitely outside the scope of science and math.

However, the workings of the devices that we use to implement the reproduction of
sound in our audio systema; are definitely bound by the laws of Physics and Math.

However, the workings of the devices that we use to implement the reproduction of sound in our audio systema; are definitely bound by the laws of Physics and Math.

Agree without reservation. For those things that we observe, and they seem "magical", it is merely that we do not have the understanding of the scientific principle(s) involved and/or lack the ability to measure them.

Lee

I know, it was just a cheap joke! :)

I don't know about "great knowledge"; but anything that will make our audio reproduction
system sound better will be grounded in science.

The devices that we use for audio playback obey the Laws of Physics; and the encoding
and processing done in digital audio obey certain laws of Mathematics.

We can't pretend that these devices are doing something "magical" that is outside the
realm of science and mathematics.

How you judge the results and how the music makes you "feel" and what your music
and audio preferences are; are definitely outside the scope of science and math.

However, the workings of the devices that we use to implement the reproduction of
sound in our audio systema; are definitely bound by the laws of Physics and Math.

There is NO DOUBT that speakers are the weakest link of the Reproduction chain.. What we should refrain from are difficult to verify statements those that are based on a belief rather than tests.. Example : 3 cheap amplifiers will be better than one expensive one.. Have any of those advancing this have actually performed this experiment? And are able to conclude with certainty that it is so?
This is actually quite well understood (from the days of active vs passive x-overs) as long as you consider some caveats.

1. You don't confound variables in your testing. If you compare very expensive SS amps with competent designed amps in the hundreds of dollars, the answer is generally yes. But if you compare tube and SS amps, then other variables may come into play (e.g. personal preference for tube distortions/euphonics).

2. Obviously the active x-over has to be designed to meet the needs of the speaker in question.

3. The amps are able to address the load needs of the drivers (this is actually less important than for some passive x-overs which can present horrendous loads for amps).

4. Lastly, proper blind testing procedures.

Active x-overs just eliminate some of the head aches passive x-overs create. In a similar vein, digital x-overs just give the opportunity to eliminate a number of head aches that analog x-overs create. In a manner of speaking Greg and John have made the same comment. The less issues you have to address, the better the problems can be addressed. However, the solution must be prudently applied and not pursued with the blind lust that more is better.

PS Syswei, the relative failure in the marketplace of active and digital x-overs has little or nothing to do with cost, since one can provide examples of speaker-amp combinations costing more while providing less. It is just a case of the marketplace dictating preferences that elevate certain paradigms over others.

PPS We can all remember inferior products bringing about the death of superior products in the marketplace.

It amazes me that people will spend $20K on a stereo amplifier, but wouldn't spend even $1500 on a 6-channel amplifier that would blow the big amp out of the water.
Do you have a $20,000 stereo amplifier and a $1,500 six channel amplifier which would blow the $20,000 stereo amplifier out of the water in mind? Would you please specify what "blow out of the water" means? What would the purchaser of the $20,000 stereo amplifier do with the extra four channels of the $1,500 six channel amplifier once he got it home?

And still the room is the weakest part in the chain of 95% of all listening setups.

John, Athena project does not ring a bell, more details pls. Obviously something that explains in "a different way" a pure stereo mic recording....so that it all the sudden needs sounded speakers to sound right. Maybe I'm just not understanding due to language barrier ?

BTW: it would be a dream, if we could mention in the facts given the relevance in terms of thresholds, that is what the human ear can actually hear/differentiate. It's cool to get physics straight, but for me it is more pratical and cooler to focus on what can be heard or not. The later saves time as well.

@Fabberyman, we should skip the discussion on amps. Pls do some level matched comparisons yourselve and then we discuss the relevance and differences between FET amps on "non exotic" Ohm loads in a different thread. For the time being, simply note, it makes more sense to have the amps after the x-over loading and controlling directly the drivers. If you are in doubt, ask yourselve why 99% of all good subwoofer are directly driven.....hence they are called "active subwoofers". Rings a bell ?

@Fabberyman, we should skip the discussion on amps...For the time being, simply note, it makes more sense to have the amps after the x-over loading and controlling directly the drivers. If you are in doubt, ask yourselve why 99% of all good subwoofer are directly driven.....hence they are called "active subwoofers". Rings a bell ?
You are preaching to the choir. I own Meridian DSP speakers and a JL Audio sub. I am simply trying to flesh out Alimentall's $20,000/$1,500 amp comment.

We can't pretend that these devices are doing something "magical" that is outside the realm of science and mathematics.

I disagree here. Neither Physics nor Mathematics is magic...but Physics and Mathematics are magical in what they reveal to us.

A while back I posted my experience with Meridian speakers as compared to the Revels with good electronics connected to both..Oddly it was deleted...I was curious as to what you feel sounds better. You seem to adore the Revels (like myself) , but you also like the Meridians...I don't. They are much less enjoyable to me.

Whats a better speaker?

Both, neither. It depends. The Revels have the better, certainly more exotic, drivers. Both have exceptional cabinetry. But the Meridian has the better crossover. The Revels are more resolving in a 'macro' kind of way, but the Meridians do better with letting you hear lower level sounds buried into a complex mix, or just at very low volumes. The Revels play loud, but the Meridians do it more effortlessly and with less fatigue factor. The Revels probably image a touch better, though I'm not sure about that one as I heard them in different rooms. If I had the $35K for the Meridians though, I'd probably buy the Studio2s and DEQX them. I asked Mark Glazer who is the chief engineer of the Revels if he could build a better Ultima with DSP and he said "Oh, of course, but is there a *market* for it".

John,

Mathematically, the TacT filters are better.

Specifically how? Have you seen the algorithms for both?

Additionally, TacT had the DRC - dynamic
room correction - capability that they pioneered. DEQX didn't have anything like it at
the time - in fact nobody did. Kal Rubinson added that Audyssey now has DRC.
It appears that DEQX has yet to master the technique of DRC.

That's because TacT is a room correction/FR correction device and the DEQX is a DSP crossover/impulse response correction device. Similar, but too different to be directly compared. If you are looking at mono amping or adding some subs and correcting your speaker/room, buy the TacT. If you are looking at eliminating passive crossovers and getting the maximum capacity from your speakers, buy DEQX. Its that simple.

The Revels probably image a touch better, though I'm not sure about that one as I heard them in different rooms.
If you are a dealer for both Meridian and Revel as you claim, why haven't you heard them in the same room, say the listening room at your audio store?

Those so-called real world problems are math equations; you solve them with math equations; the resulting solution is a math equation. It is categorically wrong to say:

Okay, then please write the math equation for building a speaker.

Both, neither. It depends. The Revels have the better, certainly more exotic, drivers. Both have exceptional cabinetry. But the Meridian has the better crossover.


How can you know that the Meridian have better crossover? Better than, what?

John,

When we were discussing the Maxx-2; you didn't even know you had to keep UNITS
consistent. You gave an equation for force that ended up with the force having units
of kg per meter. You said the force exerted on the cabinet by the speaker was the
product of the mass of the driver and excursion divided by the area of the driver.

Big deal. That was a mental slip in the midst of an argument and you clutch to it every time you get behind in an argument. You on the other hand can't understand how you change the dispersion of a speaker system by varying the crossover slope. And think that you set up a dipole speaker based on some half-wave bass note theory, rather than the concept of delayed reflections.

I would expect a grade schooler to do better than that.

Besides; John; do you mean to tell me that you know Fourier Transforms - which is
the mathematics needed here?

You always bring this stuff up when you can't win an argument with me. Which is pretty much 100% of the time. When you resort to attacking the person rather than countering his argument, you've already lost (again).

I agree ... Not THINKING of it as such does not change what it is intrinsically.. A set of math equations.. The thing has aq physical existence, thus it can be modelized and indeed that is how one build a speaker these days, ANY speaker, through modelization...

Then there is no need to ever listen to a speaker, we can simply have a laptop design and build them.

Do you have a $20,000 stereo amplifier and a $1,500 six channel amplifier which would blow the $20,000 stereo amplifier out of the water in mind?

Sure, let's just say the NAD 9060 and a Krell FPB whatever or maybe a LAMM tube amp.

Would you please specify what "blow out of the water" means? What would the purchaser of the $20,000 stereo amplifier do with the extra four channels of the $1,500 six channel amplifier once he got it home?

Blow out of the water - perform obviously better in the context of a good active crossover as a replacement for the passive one in a speaker. There are a number of distortions, modulations and energy losses that go away that the lesser amp would not have to push its way through. This would be simple to test - just take any speaker that has a simple 12, 18 or 24 dB/octave crossover with no driver compensation in it and run it both ways, active and passive using the same slopes. The clarity level is pretty obvious. I've done this with DEQX. Let's face it, there's just not THAT much difference between two well-designed amps to cover that big a difference.

How can you know that the Meridian have better crossover? Better than, what?

Better than electrically lossy and inconsistent inductors, resistors, capacitors.

If you are a dealer for both Meridian and Revel as you claim, why haven't you heard them in the same room, say the listening room at your audio store?

I sold the Revels and went back to Meridian. End of story.

You haven't submitted your math homework.

And still the room is the weakest part in the chain of 95% of all listening setups.

John, Athena project does not ring a bell, more details pls. Obviously something that explains in "a different way" a pure stereo mic recording....so that it all the sudden needs sounded speakers to sound right. Maybe I'm just not understanding due to language barrier ?

Hard to find, not sure if it was published on the net. What I am saying is that the FR of a speaker should be flat. HOWEVER, whether it is a real instrument in front of you or a speaker, the room, no matter how it is treated, will change the sound somewhat because of distance and because of room gain. This will result in a warmer sound than perfectly flat. Perfectly flat is what Audyssey does in "flat" mode and very few people like it. Most will tell you that it is too bright, too harsh and too lean in the bass. The Athena Project set out to find out what 'target curve', flat or otherwise, sounds most *natural* at the listening position.

Then there is no need to ever listen to a speaker, we can simply have a laptop design and build them.

Do you read the posts from you own thread? Did anyone say that ALL that was needed to design a speaker was knowledge of mathematics?

Do you read the posts from you own thread? Did anyone say that ALL that was needed to design a speaker was knowledge of mathematics?

That appears to be Greg's and Faberryman's assertion. It's all a 'math equation'. I disagree. You use math to solve problems, but humans are the ones that decide how to do that and what problems are most important and how, in the real world, the result is. Either it's a math equation or a real world problem requiring human problem solving skills. You can't have it both ways.

We can't pretend that these devices are doing something "magical" that is outside the
realm of science and mathematics.

I disagree here. Neither Physics nor Mathematics is magic...but Physics and Mathematics are magical in what they reveal to us.

Nice one Dennis. I commend your skill in sculpting an argument where for the most part you already agree. ;) Now only if so many weren't so skilled in this... http://www.hometheatershack.com/forums/images/smilies/dizzy.gif




To be sure though, that really was a deep assessment of the situation. :p

http://www.htguide.com/forum/images/smilies/btakecover.gif

John

The Mathematics, DeQX are , were said by all, to be tools.. Can you show me where anyone said that Mathematics were sufficient to build a speaker? Come On!!!! What we keep on repeating and that you childishly refuse to accept or try to distort is that a speaker can be modelized through mathematics.. The behavior of the driver can be modelized... What do you think the DeQX do? How do you think it corrects for driver aberrations? What do you think any digital crossover does? What do you think a crossover slope is? 48 dB per octave is a mathematical representation of the slope (another mathematical concept) of a crossover Isn't that maths?
Now the job of the speaker designer /engineer/scientist is to find the best set of compromises to approach an ideal.. What are you trying to refute in this.. Please do tell us? if you simply need us to agree with you on all your faslseties you are knocking at the wrong door.. Bullying tactics, Puerile behavior or distortion notwithstanding you have the facts wrong on this... that takes us away from the discussion at hands strangely enough thanks to you the original poster which is somewhat unusual... we were trying to discuss the merits of Digital Crossover and in some ways of the active approach which is quite valid in my opinion and if applied properly should IMHO leads to better results than the current more orthodox passive crossovers approach... Notice the "leads" for now the results may not be there.. I haven't heard that many Digital Active Crossover systems.. so I don't know how they compare to the current SOTA... So let us try to reset if your position is about getting the last word ...well you will and the thread will simply die on your word ...else , I believe this is be a very interesting thread.. I want to know more about people experience with Digital Active Crossovers and if you will speakers as well and tell us how they compare to the passive approach... You will help by dialing down the hype machine and maybe not mentioning the X + a NOT vowel thing at all :) ..

Either it's a math equation or a real world problem requiring human problem solving skills. You can't have it both ways.
This is a classic example of the logical fallacy of false dilemma which permeates your thinking, and leads you to hyperbolic positions and untenable conclusions. Contrary to your assertion, speaker design can be both a math equation and a real world problem requiring human problem solving skills.

Sure, let's just say the NAD 9060 and a Krell FPB whatever or maybe a LAMM tube amp.

Blow out of the water - perform obviously better in the context of a good active crossover as a replacement for the passive one in a speaker. There are a number of distortions, modulations and energy losses that go away that the lesser amp would not have to push its way through. This would be simple to test - just take any speaker that has a simple 12, 18 or 24 dB/octave crossover with no driver compensation in it and run it both ways, active and passive using the same slopes. The clarity level is pretty obvious. I've done this with DEQX. Let's face it, there's just not THAT much difference between two well-designed amps to cover that big a difference.
So the NAD 9060 blows the Krell FPB out of the water, but only if you also buy a DEQX and then go home and take your speakers apart, remove the crossovers, wire in the DEXQ, learn how to use it, buy some test equipment and learn how to use it, and futz around hoping to find some settings which make your disassembled speakers both measure better and sound better than what you remember (if you can) your speakers originally sounded like. But now we are not really comparing amplifiers any more are we? It's no wonder more people don't do as you suggest. What are they thinking? How many customers have you convinced that this is a good alternative?

This is a classic example of the logical fallacy of false dilemma which permeates your thinking, and leads you to hyperbolic positions and untenable conclusions. Contrary to your assertion, speaker design can be both a math equation and a real world problem requiring human problem solving skills.

You were the one that said that designing a speaker is just a math equation, so I'm asking for the equation as maybe I'd like to build a speaker. Otherwise, it's all about human 'fuzzy logic' decisions/tradeoffs and the math is just a tool, not the problem itself.

So the NAD 9060 blows the Krell FPB out of the water, but only if you also buy a DEQX and then go home and take your speakers apart, remove the crossovers, wire in the DEXQ, learn how to use it, buy some test equipment and learn how to use it, and futz around hoping to find some settings which make your disassembled speakers both measure better and sound better than what you remember (if you can) your speakers originally sounded like. But now we are not really comparing amplifiers any more are we? It's no wonder more people don't do as you suggest. What are they thinking? How many customers have you convinced that this is a good alternative?

Or you could just use a $300 Behringer with the NAD and still be well under the price of an uber amp for higher performance, assuming there is no driver compensation. DEQX is just handier because it does the driver compensation and essentially optimizes driver behavior (well, corrects for it) before the crossover is engaged.

John

The Mathematics, DeQX are , were said by all, to be tools.. Can you show me where anyone said that Mathematics were sufficient to build a speaker? Come On!!!!

Did you miss where it was said that it is simply an equation? That if you 'cheat' by removing some of the problems, that it throws the equation off and you end up with a poorer result?

What we keep on repeating and that you childishly refuse to accept or try to distort is that a speaker can be modelized through mathematics.. The behavior of the driver can be modelized... What do you think the DeQX do? How do you think it corrects for driver aberrations? What do you think any digital crossover does? What do you think a crossover slope is? 48 dB per octave is a mathematical representation of the slope (another mathematical concept) of a crossover Isn't that maths?

Sure, but the math is a tool. The process itself is not an equation. It's like you saying that driving to work is an equation. And that if you put anti-lock brakes on your car, that it is more dangerous because it takes away one of the problems with driving.

Or you could just use a $300 Behringer with the NAD and still be well under the price of an uber amp for higher performance, assuming there is no driver compensation. DEQX is just handier because it does the driver compensation and essentially optimizes driver behavior (well, corrects for it) before the crossover is engaged.
Of course, you still have to take the NAD and the Behringer home and take your speakers apart, remove or bypass the crossovers, wire in the Berhringer, learn how to use it, buy some test equipment and learn how to use it, and futz around hoping to find some settings which make your disassembled speakers both measure better and sound better than what you remember (if you can) your speakers originally sounded like. But then we aren't really comparing amplifiers, are we?

What do you think any digital crossover does? What do you think a crossover slope is? 48 dB per octave is a mathematical representation of the slope (another mathematical concept) of a crossover Isn't that maths?

This is a great point. We often discuss a digital crossover as if it's the same as implementing an analog crossover. It's actually a pair of complimentary filters which approximates the performance of an nth order crossover, where n == an integer value of 6dB / octave.

So we would say that a 48dB digital crossover approximates the performance of an 8th order analog crossover. It's not perfect, but it's damn close.

But then we aren't really comparing amplifiers, are we?

Nope, we're comparing one way of doing it versus another. Context.

This is a great point. We often discuss a digital crossover as if it's the same as implementing an analog crossover. It's actually a pair of complimentary filters which approximates the performance of an nth order crossover, where n == an integer value of 6dB / octave.

So we would say that a 48dB digital crossover approximates the performance of an 8th order analog crossover. It's not perfect, but it's damn close.

Sure, but even an analog crossover is approximating a theoretical crossover because the parts aren't perfect and the impedances aren't constant. The digital crossover will be closer to theoretically perfect.

I disagree here. Neither Physics nor Mathematics is magic...but Physics and Mathematics are magical in what they reveal to us.

Our current physics will do until the next set of even better theories surpass them. It took about 250 years to rewrite Newton with General Relativity. How long before General Relativity is rewritten (as an example).

Pardon me being slightly tongue cheek here. Physics (as you know very very well) is ever evolving :D

Nope, we're comparing one way of doing it versus another. Context.
The question was a rhetorical one so that you would reflect on what the implied answer to the question must be. You correctly identified the answer as "Nope." So the $1500 six channel amp doesn't really blow the $20,000 amp out of the water. You haven't tried using the $20,000 amp in lieu of $1500 amp and made measurements to determine which is the better amp.

Sure, but even an analog crossover is approximating a theoretical crossover because the parts aren't perfect and the impedances aren't constant. The digital crossover will be closer to theoretically perfect.

Maybe yes, maybe no.

It comes down to the implementation and whether or not you can live with the attendant artifacts. Some of them are very very very low (ie the 22bit range).

John

I rarely lose my temper on any thread but seeing your BS and steadfast refusal to concede on even the smallest point which is by the way a fact I am off your thread> You can BS all you want and leave yourself the impression of having won but you and everybody's in this forum know you are BSing big time....The facts are there and no amount of distortion spin and plain BS will not change it I am off do as you please with your thread... I have rarely seen such an immature display of intellectual dishonesty...

Maybe yes, maybe no.

It comes down to the implementation and whether or not you can live with the attendant artifacts. Some of them are very very very low (ie the 22bit range).

Well, true, I was assuming bit depth at least equal to or better than the incoming signal. I still hear more artifacts in a passive crossover that I refer to as a type of signal compression that I don't hear on Meridians for instance.

BTW, I know you're on the 'ins' with Meridian, but have they told you they use 48dB/octave crossovers in the DSP7200? I can't find a reference to it either way. I am impressed by them, nice leap over the older models. I wish they weren't so expensive though.........

I rarely lose my temper on any thread but seeing your BS and steadfast refusal to concede on even the smallest point which is by the way a fact I am off your thread> You can BS all you want and leave yourself the impression of having won but you and everybody's in this forum know you are BSing big time....The facts are there and no amount of distortion spin and plain BS will not change it I am off do as you please with your thread... I have rarely seen such an immature display of intellectual dishonesty...

Could you please explain what I am BSing about? And what point I am supposed to concede? I mean, I don't mind conceding if I'm wrong. You can not say that being able to correct, for instance, time in a speaker design electrically is going to cause some bad mojo because 'mother nature' can't stand having, what was it, an 'under determined equation' (?). That's why I say a speaker design ≠ an equation. Not without being overly simplistic. DSP is not a 'cheat'. It's an advancement. It does not through nature out of balance or equations out of whack. It solves problems. Elegantly. Leaving speaker designers to focus on other things that DSP can't solve. I'm sorry if you can't follow the logic on this, but there's no need to be angry, nor to lob insults.

Well, true, I was assuming bit depth at least equal to or better than the incoming signal. I still hear more artifacts in a passive crossover that I refer to as a type of signal compression that I don't hear on Meridians for instance.

BTW, I know you're on the 'ins' with Meridian, but have they told you they use 48dB/octave crossovers in the DSP7200? I can't find a reference to it either way. I am impressed by them, nice leap over the older models. I wish they weren't so expensive though.........

It's probably similar to the 8Ks.

One woofer full to the midrange, one with an analog lowpass at 400Hz or so. The 8000 cascades even more, with one lowpassed at 400Hz, one lowpassed about 800Hz (per side). The analog lowpass could be as simple as an appropriately valued capacitor.

Then 48dB/octave woofer to mid. 48 dB/octave mid to tweeter. Complimentary filter pairs here of course.

You were the one that said that designing a speaker is just a math equation, so I'm asking for the equation as maybe I'd like to build a speaker. Otherwise, it's all about human 'fuzzy logic' decisions/tradeoffs and the math is just a tool, not the problem itself.
John,

It's easy!!! For all the drivers, you write Newton's 2nd Law of Motion: F = ma.
That is Force = mass times acceleration. For the linear motor in the driver; you
need Faraday's Law. For the air in the box and surrounding the speaker; you need
the wave equation.

It's not a single equation; the equations are coupled. For example, the position of the
cone of the driver becomes a boundary condition for the wave equation describing the
motion of the air external to the driver.

Again, more complex systems than loudspeakers are modeled mathematically. Boeing
doesn't do much wind tunnel testing these days; they can design airliners on computer.
Likewise, my lab and our sister lab have not done a test in 16 years; because we can
simulate them on the computer.

Did you miss where it was said that it is simply an equation? That if you 'cheat' by removing some of the problems, that it throws the equation off and you end up with a poorer result?
John,

What are you throwing out John?

Sure, but the math is a tool. The process itself is not an equation. It's like you saying that driving to work is an equation. And that if you put anti-lock brakes on your car, that it is more dangerous because it takes away one of the problems with driving.

If you are talking about unconstrained degrees of freedom - those ARE a problem in
computational physics. If the system can "move" or "do something" and you have not
given the system a rule to follow to dictate that motion; then your simulation will just
give random numbers.

A-ha. So you're saying you *could* model speaker design as opposed to 'it's an equation'. Until it actually *is* a series of equations, a full simulation, there is nothing to get 'under determined' in the simulation that doesn't exist. Because if you actually do a real simulation, you'll find that adding advanced DSP into the simulation will cause some of it to get 'zeroed out' and the simulation suddenly become simpler, just as it is in real life.

Such a simulation would have to have all the driver measurements for every driver in existence, as well as the ability to custom order or design drivers from scratch, shape the cabinet, make it have some WAF factor for those who have wives, etc, etc. It doesn't exist, therefore, humans still do all the hard work and use tools to accomplish their goals, the most advanced tool now available being DSP crossover/impulse response correction, aka DEQX.

Our current physics will do until the next set of even better theories surpass them. It took about 250 years to rewrite Newton with General Relativity. How long before General Relativity is rewritten (as an example).

Pardon me being slightly tongue cheek here. Physics (as you know very very well) is ever evolving :D
John,

Yes - at the level of the attempts to unify all the forces; then yes it is evolving. That is
a few years ago we had 4 basic forces; gravity, the strong nuclear force [ holds the
nucleus together and is responsible for the energy that nuclear reactors release ], the
weak nuclear force [ responsible for some radioactive decay ], and the Coulomb force
[ which is the force that provides the force between charged particles - like the nucleus
and the electrons; and hence is responsible for all chemistry. Any chemical reaction,
like combustion that releases energy is due to the this force ].

With the discovery of the intermediate vector boson or "W" some time back; we now
know that the weak nuclear and the Coulomb force are two manifestations of the same
force - now called the electro-weak force.

The aim is to unify all these forces; to say that all are just different manifestations of one
force. That is called Grand Unification.

However, physics on the scale of loudspeakers, and how they move, the electric forces
that drive them, how the air responds.... is all very well known physics that has been
known for over a hundred years. There has been nothing new in the understanding of
the physics that underlie loudspeakers since the mid 19-th century.

If you are talking about unconstrained degrees of freedom - those ARE a problem in
computational physics. If the system can "move" or "do something" and you have not
given the system a rule to follow to dictate that motion; then your simulation will just
give random numbers.

Yes, but speaker design still isn't an equation. The DEQX box obviously has 'rules' to generate a proper, though not necessarily perfect result. When I say the *engineer* has more degrees of freedom in solving the 'equation' (really a problem), such as the ability to use different size/shape/materials/impedances and crossover slopes for the drivers than he did before. More ways of solving the problem.

In speaker design, every choice you make essentially dictates another choice for you. Start down one path and you almost automatically end up someplace, often where you don't wan to be. B&W expresses this in their 800D white paper. Bringing DSP means that you can more easily end up where you want to be because each choice allows more 'degrees of freedom' (pathways) to achieve the solution you want and 'solve' the 'equation'.

Could you please explain what I am BSing about? And what point I am supposed to concede? I mean, I don't mind conceding if I'm wrong. You can not say that being able to correct, for instance, time in a speaker design electrically is going to cause some bad mojo because 'mother nature' can't stand having, what was it, an 'under determined equation' (?). That's why I say a speaker design ≠ an equation. Not without being overly simplistic. DSP is not a 'cheat'. It's an advancement. It does not through nature out of balance or equations out of whack. It solves problems. Elegantly. Leaving speaker designers to focus on other things that DSP can't solve. I'm sorry if you can't follow the logic on this, but there's no need to be angry, nor to lob insults.
John,

Frantz is EXACTLY CORRECT!!! Just because YOU don't understand the science
and the mathematics - don't claim that mathematical simulation is being overly simplistic.

Just because you don't understand constraints and degrees of freedom - there are plenty
of engineers and scientists who do. You are NOT some great expert and anything outside
your understanding must be baloney.

There are people that know far more that you do about mathematics, physics, and the
design and operation of audio equipment. We have members here that have college
degrees, and even advanced degrees in the sciences here.

You don't become a fellow of the National Academy of Science and Engineering; or
even the Audio Engineering Society by being an audio salesman for 20 years.

John,

Frantz is EXACTLY CORRECT!!! Just because YOU don't understand the science
and the mathematics - don't claim that mathematical simulation is being overly simplistic.

There is no speaker design simulation!

Just because you don't understand constraints and degrees of freedom - there are plenty
of engineers and scientists who do. You are NOT some great expert and anything outside
your understanding must be baloney.

So why do you have problems coming up with better reasoning than 'baloney'?.

There are people that know far more that you do about mathematics, physics, and the
design and operation of audio equipment. We have members here that have college
degrees, and even advanced degrees in the sciences here.

But few know more about what's going on in the field itself. You certainly don't. You can't even answer the basic challenges I give you, such as explaining why TacT is better than DEQX.

You don't become a fellow of the National Academy of Science and Engineering; or
even the Audio Engineering Society by being an audio salesman for 20 years.

And you don't become an expert on everything by getting a PhD in math. Want to explain your 'half-wave' theory of setting up dipoles again for us?

Yes, but speaker design still isn't an equation. .
John.

It is not a single equation - but it IS a set of coupled differential equations.

Why don't you take a few years [ or decades ] to get a degree in engineering and / or
science with the requisite mathematics? Then maybe we can discuss this.

You can hand wave all you want - but in the final analysis; every component in an audio
system obey physical laws that can be cast as equations. I don't know why you can't
understand that!!!

How do you think we launch spacecraft that can rendezvous with the outer planets many
years later? Do we take your approach and say, "Oh, a spacecraft is not an equation" or
"Oh, a planet is not an equation". NO - the motion of both spacecraft and planets can
be described by mathematics; and by solving those equations - we can put a spacecraft
in a region of space nearby those planets.

You don't know how to do that; but just because you don't know how to do it; don't say
that others don't know how to do it or that it can't be represented that way.

A-ha. So you're saying you *could* model speaker design as opposed to 'it's an equation'. Until it actually *is* a series of equations, a full simulation, there is nothing to get 'under determined' in the simulation that doesn't exist. Because if you actually do a real simulation, you'll find that adding advanced DSP into the simulation will cause some of it to get 'zeroed out' and the simulation suddenly become simpler, just as it is in real life.
John,

There ARE computer programs that can model this in existence. A speaker is basically
a mechanical system. There are computer programs that can EASILY handle such
mechanical systems. My lab is responsible for one of the most used and most
advanced; DYNA3D:

https://www-eng.llnl.gov/mdg/mdg_codes_dyna3d.html

DYNA3D has been used in the design of jet engines; like that pictured, and has been
used to analyze the earthquake response of the Golden Gate and Oakland-Bay bridges.
It could CERTAINLY handle a loudspeaker driver.

Now what are blathering about something getting "zeroed out" when you use DSP.
Be specific - WHAT gets "zeroed" because of DSP?


Such a simulation would have to have all the driver measurements for every driver in existence, as well as the ability to custom order or design drivers from scratch, shape the cabinet, make it have some WAF factor for those who have wives, etc, etc. It doesn't exist, therefore, humans still do all the hard work and use tools to accomplish their goals, the most advanced tool now available being DSP crossover/impulse response correction, aka DEQX.

No - you don't have to know about every driver in existence. YOU tell the computer
what the driver in the speaker you are designing looks like - and what its properties are;
compliance of the cone suspension, for example. It computes how that driver moves.
Couple that to a wave equation, and you can calculate the soundfield.

Don't like the result? Change the design of the driver - change the compliance and
redo the calculation. Once you get something you like; THEN you can hand the specs
over to craftsmen to actually make the part.

This is how jet engines, airliners, cars....LOTS of things are designed.

Why would you "think" that you would need to know the parameters of every driver
in existence??? Why would you even consider that you needed that? You are designing
a tweeter for NHT; why would you need to know what a woofer being made in Germany
looks like?

Come on, John; put on your "thinking cap".

It is not a single equation - but it IS a set of coupled differential equations.

A very large set of possible equations that are, as yet, a figment of your imagination. Unless you'd like to link to them or take a few pages and actually write these equations.

Why don't you take a few years [ or decades ] to get a degree in engineering and / or
science with the requisite mathematics? Then maybe we can discuss this.

Why don't you get off your high horse and and stop spouting pseudo-science?

You can hand wave all you want - but in the final analysis; every component in an audio
system obey physical laws that can be cast as equations. I don't know why you can't
understand that!!!

I do understand that, but I also understand that DSP gives you more room to maneuver and come back with a closer to ideal result.

How do you think we launch spacecraft that can rendezvous with the outer planets many
years later? Do we take your approach and say, "Oh, a spacecraft is not an equation" or
"Oh, a planet is not an equation". NO - the motion of both spacecraft and planets can
be described by mathematics; and by solving those equations - we can put a spacecraft
in a region of space nearby those planets.

That is a much simpler set of equations than creating one for building a speaker. Those equations and simulations actually exist, the one you keep talking about for speakers does not.

You don't know how to do that; but just because you don't know how to do it; don't say
that others don't know how to do it or that it can't be represented that way.

I didn't say that. I'm saying the equations don't exist and you're just making stuff up to try to talk above everyone. Doesn't work with me. DSP solves problems, it doesn't create underdetermined equations.

There is no speaker design simulation!
John,

I could setup a calculation of a loudspeaker driver the same way that jet engine
simulation was set up. Do you honestly think a loudspeaker driver is more complex
than a jet engine?


But few know more about what's going on in the field itself. You certainly don't. You can't even answer the basic challenges I give you, such as explaining why TacT is better than DEQX.

Sure - I already gave you that answer. The mathematics implemented in the TacT is
WAY WAY better than what the DEQX has. Additionally, as I stated, TacT has mastered
Dynamic Room Correction [DRC] and Audyssey has followed suit. DEQX is mssing in
action on that one.

And you don't become an expert on everything by getting a PhD in math. Want to explain your 'half-wave' theory of setting up dipoles again for us?

That theory is CORRECT - the fact that YOU don't understand it not withstanding.

John, you've proved time and again that you are absolutely clueless on the mathematics
of the wave equation - so it's no wonder you don't understand that theory.

Get an education John - and quit telling people who are more educated than you are that
they don't know what they are talking about.

Over and out.

There ARE computer programs that can model this in existence. A speaker is basically
a mechanical system. There are computer programs that can EASILY handle such
mechanical systems. My lab is responsible for one of the most used and most
advanced; DYNA3D:

Sure, how many are programmed to do it? None.

Now what are blathering about something getting "zeroed out" when you use DSP.
Be specific - WHAT gets "zeroed" because of DSP?

Time/phase, for one.

No - you don't have to know about every driver in existence. YOU tell the computer
what the driver in the speaker you are designing looks like - and what its properties are;
compliance of the cone suspension, for example. It computes how that driver moves.
Couple that to a wave equation, and you can calculate the soundfield.

So, in the end, you still have a human using a tool, rather than a 'set of equations' determining the result.

Come on, John; put on your "thinking cap".

Sure. You put on your 'logic cap' first. And your 'reasoning slippers'. A 'reality cape' might be helpful.

John,

I could setup a calculation of a loudspeaker driver the same way that jet engine
simulation was set up. Do you honestly think a loudspeaker driver is more complex
than a jet engine?

A jet engine may be more complex than a speaker driver, but not as complex as a speaker system. Jet engines are pretty simple creatures.


Sure - I already gave you that answer. The mathematics implemented in the TacT is
WAY WAY better than what the DEQX has.

Because you say so? Have go gone through all the lines of code in both? Specifics, please, not just 'hope'.

Additionally, as I stated, TacT has mastered
Dynamic Room Correction [DRC] and Audyssey has followed suit. DEQX is mssing in
action on that one.

DEQX is not room correction! It is a speaker correction device with parametric EQ as well. The computer in my car's engine doesn't play the violin.

That theory is CORRECT - the fact that YOU don't understand it not withstanding.

Oh, I understand what you think you're doing, but you are, again, being incredibly simplistic, looking to math rather than psychocoustics.

John, you've proved time and again that you are absolutely clueless on the mathematics
of the wave equation - so it's no wonder you don't understand that theory.

Get an education John - and quit telling people who are more educated than you are that
they don't know what they are talking about.

Over and out.

For a bright guy, you keep trying to show how dumb you are. Lots of bluster, but no actual facts.

It'd be nice to see the personal attacks/diatribes end. Perhaps BOTH sides could simply ignore the baiting and let it (finally) end.

I personally do not like the dynamic loudness in the Audyssey or the Tact gear. Maybe my ears have gotten used to how my system sounds at various volume levels.

Speaker/driver correction and even more so PEQ for room anomalies below 200hz, that's another matter.

BTW, I found this 4-way DSP crossover w/up to 48dB/octave slopes -

http://www.ashly.com/protea424c.html

I also saw that there is/was a company working on a 5-way DEQX solution for the Magico Ulimate speaker. Not that it would need it, right ;) ;) ;)

I personally do not like the dynamic loudness in the Audyssey or the Tact gear. Maybe my ears have gotten used to how my system sounds at various volume levels.

I was speaking with NAD about this and they said that Audyssey Dynamic EQ/Loudness comes in too aggressively and quickly, so they had it toned way down to be much more subtle. I think with mass market technologies, people like to hear what they are buying, the same reason subs and rears always seem to be 5-10dB too loud when we go to peoples' homes.

An interesting exchange: An educated and practicing physicist arguing with a guy who owns an audio store in Albuquerque on who knows more about modeling loudspeakers, jet engines and spacecraft and the audio store guy refuses to acknowledge truth. John, your already diminished credibility continues to shrivel !!

Audioguy ... would be nice to see the attacks end on ALL sides.

I've learned quite a bit from John's posts, as well as our Physicist's

Better than electrically lossy and inconsistent inductors, resistors, capacitors.


You have not show any proof of this yet.

Audioguy ... would be nice to see the attacks end on ALL sides.

I've learned quite a bit from John's posts, as well as our Physicist's

I'm with you. While heated, these debates do lead to interesting things being discussed and I have learned a lot personally.

Sean

Well, true, I was assuming bit depth at least equal to or better than the incoming signal. I still hear more artifacts in a passive crossover that I refer to as a type of signal compression that I don't hear on Meridians for instance..........


Again, HOW do you know that the artifacts you say you hear is because of a passive crossover filter?
Btw, I heard a Meridian set-up a couple of weeks ago, is sounded like crap so probably it was the active crossover filter that made it sound bad...or could it be something else...?

You have not show any proof of this yet.

I don't have a 'proof' handy, but it's pretty intuitive. Capacitors, inductors, resistors all affect the audio signal coming through, all are lossy (convert signal to heat), all have varying levels of precision, all are pretty static in their capabilities for adjustment, all will modulate their crossover frequencies based on the varying impedances of the drivers and musical content, etc, etc, etc.

Kinda surprised your not fervently on my side with this.

An interesting exchange: An educated and practicing physicist arguing with a guy who owns an audio store in Albuquerque on who knows more about modeling loudspeakers, jet engines and spacecraft and the audio store guy refuses to acknowledge truth. John, your already diminished credibility continues to shrivel !!

Says the other audio store guy.......

Again, HOW do you know that the artifacts you say you hear is because of a passive crossover filter?

I'm not 100% positive. However, I hear this sound as a part of just about every passive speaker I hear, yet do not with digital speakers. The improvement in dynamics or the 'appearance' of improved dynamics seems pretty obvious to me.

Btw, I heard a Meridian set-up a couple of weeks ago, is sounded like crap so probably it was the active crossover filter that made it sound bad...or could it be something else...?

In your opinion. If Meridian has a flaw, it's that they don't use the very best and most pistonic SEAS drivers available on their tower speakers, though they do use the more expensive and more exotic SEAS Excels on their inwalls, not to mention a ribbon tweeter which, I assume, probably sounds pretty decent. I'd love to hear those drivers in their free standing units. The DSP 7200s are quite a bit better than the MUCH older DSP5000/5500/6000 models. So I assure you, whatever you think of the Meridians, it's not the DSP filtering causing the issue. Room acoustics or you just don't like their sonic sound based on the drivers they've chosen.

Says the other audio store guy.......

(1) I'm not an audio store guy (about 6 years ago I did represent SigTech [may they rest in peace] as a Director of Marketing) and (2) that point notwithstanding, and while I do have a degree in applied math with a minor in Mechanical Engineering (about 483 years ago) I would sure bow to the likes of Morbius when it comes to matters of simulation of things like speakers and spaceships.

(1) I'm not an audio store guy (about 6 years ago I did represent SigTech [may they rest in peace] as a Director of Marketing) and

I honestly thought you worked at a regional chain store or something based on a few things you said.

(2) that point notwithstanding, and while I do have a degree in applied math with a minor in Mechanical Engineering (about 483 years ago) I would sure bow to the likes of Morbius when it comes to matters of simulation of things like speakers and spaceships.

Of course but that wasn't the argument. There is no 'speaker simulator' or any set of equations to govern true speaker design. We have tools that we use to speed and refine aspects of the process and to solve problems, but that's a different thing from diminishing it a simple math problem. Or even a complex one because the simulations don't exist.

There is no ... set of equations to govern true speaker design.
Does "true speaker design" differ from the regular type of speaker design speaker manufacturers engage in?

Does "true speaker design" differ from the regular type of speaker design speaker manufacturers engage in?

Do you ever do anything other than ask quippy single line questions?

It's easy to ask questions when you don't know anything, yet want to appear relevant.

And the answer is 'no'. Aside from maybe a few companies that plug in a few driver parameters and just insert the calculated crossover without testing it. If such a company exists. I imagine even Bose and JBL and Klipsch must listen to their speakers, not that you can tell from the results.

Flicker: Do you ever sing, or you know… play any instrument?
Angelo: F**king guitar.
Flicker: Is that a special kind of guitar?
Angelo: No, it's regular… I studied as a kid, but then I broke it over my brother's head and I went to work.

I honestly thought you worked at a regional chain store or something based on a few things you said.

Of course but that wasn't the argument. There is no 'speaker simulator' or any set of equations to govern true speaker design. We have tools that we use to speed and refine aspects of the process and to solve problems, but that's a different thing from diminishing it a simple math problem. Or even a complex one because the simulations don't exist.

From Google :

www[dot}aes[dot].org/e-lib/browse[dot]cfm?elib=9917
www[dot]educypedia[dot]be/electronics/easoftaudio[dot]html
www[dot]sonicdesign[dot]se/calsinfo[dot]html

This thread on DIYAudio list a few more

www[dot]diyaudio[dot]com/forums/showthread/t-35212[dot]html


Oh yes they exist, there are quite a few , some free... No guarantee of great results but it would be hard to find a speaker designer nowadays not using one of these software

-B<

Oh yes they exist, there are quite a few , some free... No guarantee of great results but it would be hard to find a speaker designer nowadays not using one of these software

-B<

Oh, of course, but computer-aided design is different from computer designed :)

The CALSOD program looks pretty cool though.

Oh yes they exist, there are quite a few , some free... No guarantee of great results but it would be hard to find a speaker designer nowadays not using one of these software
PARTIAL LIST OF INTERNATIONAL CALSOD USERS

Barlow Associates Australia
Elecoustics Australia
NOVA Sound Australia
M.P. & C. P.V.B.A. Belgium
A.E.D. P.V.B.A. Belgium
Bell Northern Research Canada
Novatel Communications Canada
Electrolab Denmark
Veng Audio Denmark
B & W Loudspeakers England
Canon Loudspeakers England
Carlsbro Electronics England
Martin Audio England
NAD Electronics England
Cator Finland
Gradiente Finland
Cabasse Electroacoustics France
Gaertner Consulting France
Grundig Germany
Hi-Tech GmbH Germany
Nokia Graetz Germany
Proraum Germany
Solton Music Germany
Teufel Germany
Willi Studer Germany
Elina S.A. Greece
Soza Manufactures Greece
R & S Electronics India
Chario Loudspeakers Italy
Oyster s.a.s. Italy
Acoustic Control Mexico
A.J. van den Hul Netherlands
Duran Audio Netherlands
Omnitronics Netherlands
G & L Norway
Volvo Sweden
Volken Engineering Switzerland
Magnepan USA
Marantz USA
Snell Acoustics USA
Sterling Sound USA

Gosh, Even NAD uses computer simulations to design its loudspeakers. As a dealer for NAD, I'm surprised Alimentall didn't know that. But then again it is understandable since he denies that computer simulations for speaker design exist. It must not be "true speaker design."

Oh, of course, but computer-aided design is different from computer designed :)

Hmmm....
There is no speaker design simulation!

Gosh, Even NAD uses computer simulations to design its loudspeakers. As a dealer for NAD, I'm surprised Alimentall didn't know that.

NAD doesn't design speakers. NAD of England is likely the importation company. The few NAD speakers in existence are designed by Paul Barton, who, I'm sure, does use computer aided design as well.

Hmmm....

Very powerful stuff, though I'm talking about where you push a button and the computer spits out a speaker design from the ground up.

NAD doesn't design speakers. NAD of England is likely the importation company. The few NAD speakers in existence are designed by Paul Barton, who, I'm sure, does use computer aided design as well.
He might even use speaker design simulation...but wait,
There is no speaker design simulation!

Mr Alimentall

I use Active Crossovers ( Behringer) with DIY speakers. My friends and I like the results. I am a little confused I have been following this thread with interest I thought you said that there was no simulation for speakers, there are... I don't remember someone posting that speakers were designed by Computer with no human intervention.. Drivers are commonly defined by equations in fact that is where The Thiele-Small parameters are derived from.. and when input in a Speaker Simulation Program allow you to have a pretty good idea of the performance of your designs.. You need then to listen and make proper correction... That is the way, these days, everyone from DIY, the large PRO manufacturers like Dynaudio or any HiFi Audio brands design and produce their loudspeakers, I did just that for my car system and my Home Theater...
I will now continue to lurk...

Mr Alimentall

I use Active Crossovers ( Behringer) with DIY speakers. My friends and I like the results. I am a little confused I have been following this thread with interest I thought you said that there was no simulation for speakers, there are... I don't remember someone posting that speakers were designed by Computer with no human intervention.. Drivers are commonly defined by equations in fact that is where The Thiele-Small parameters are derived from.. and when input in a Speaker Simulation Program allow you to have a pretty good idea of the performance of your designs.. You need then to listen and make proper correction... That is the way, these days, everyone from DIY, the large PRO manufacturers like Dynaudio or any HiFi Audio brands design and produce their loudspeakers, I did just that for my car system and my Home Theater...
I will now continue to lurk...

Sorry, I started off by saying that speaker design is not just an 'equation' and got dragged into the simulation part. The program you reference is pretty cool at simulating different design choices, but it only gets us part way there.

Ironically, the same sort of math 'uncertainty' that exists in DEQX measuring and correcting a speaker would naturally exist in a simulation program in greater amounts because it's theoretical, not even based on measurement.

Keep in mind that the difference between DEQX and even the most advanced simulation program is that the DEQX actually measures the real performance of the driver in the cabinet, then applies impulse response correction and displays the unsmoothed FR response of the drivers which make it painfully obvious where the crossover must go, plus or minus a bit. It's amazing how little latitude there is with many speakers. Cone resonance is one of the big factors in whether we like or dislike a speaker, so it's critical to know this when designing a speaker. I've heard speakers that measure beautifully, but are harsh because of cone resonances that simply weren't factored in properly. This is why I think any of the programs are too primitive to design a speaker with little human intervention.

Kinda surprised your not fervently on my side with this.


No, that because I don't believe in "box thinking". It's like those people that say a electrostatic speakers dont' have "boxsound" because thay don't have the same boxdesign like ordinary speakers. The problem is that if one believe this, without checking with reality, one use "box thinking".
The reality is that electrostatic speakers also can have "boxsound", because this have nothing to do with a box but vibration that can be anywhere.

I would like to know what the equation is for WAF. Then we could build the perfect speaker right?

Why does it always end up in the realm of the fairies? WHO actually designs their speakers using similar techniques to sending a space probe out into the universe.

Normally I would expect to see disagreement on the premise that measurements tell all, suddenly we are building a speaker TOTALLY in cyberspace and have it all nutted out.

On the question of loudness contours (or whatever the expression was, mind is blank right now), and that the Tact has it and the deqx doesn't. Well using a deqx I have not heard either the tact nor audessy implementation, but honestly it is NOT such a big deal. It is a completely trivial matter to do a bit of remote tweaking of relative bass, mid and treble levels, and I have 99 memories (plus four different profiles) that easily accomplish that task.

And it (being able to adjust for differing vol levels) either by auromated Tact or manual deqx can be quite valuable at times.

Is this a case of where automatic (Tact) is bad vs manual (deqx) is good? Only mucking about here, the argument often is that automated solutions are bad....depend on who you're arguing with I spose.

I'm not 100% positive. However, I hear this sound as a part of just about every passive speaker I hear, yet do not with digital speakers. The improvement in dynamics or the 'appearance' of improved dynamics seems pretty obvious to me.


Sorry, I don't believe you at all. If you did a blindtest between speaker, passive and digital active speakers, I can put a big sum och cash that you will NOT get 100% right.



In your opinion. If Meridian has a flaw, it's that they don't use the very best and most pistonic SEAS drivers available on their tower speakers, though they do use the more expensive and more exotic SEAS Excels on their inwalls, not to mention a ribbon tweeter which, I assume, probably sounds pretty decent. I'd love to hear those drivers in their free standing units. The DSP 7200s are quite a bit better than the MUCH older DSP5000/5500/6000 models. So I assure you, whatever you think of the Meridians, it's not the DSP filtering causing the issue. Room acoustics or you just don't like their sonic sound based on the drivers they've chosen.


Again, you THINK that digital active crossover is the best and if the speaker don't work, it must be something else. The problem is that you have made up your mind that "this is the best" and will stand by it even when it is not a logical choose.

Sorry, I don't believe you at all. If you did a blindtest between speaker, passive and digital active speakers, I can put a big sum och cash that you will NOT get 100% right.

Again, you THINK that digital active crossover is the best and if the speaker don't work, it must be something else. The problem is that you have made up your mind that "this is the best" and will stand by it even when it is not a logical choose.
It is surprising to see even NIN74 disagreeing with Alimentall. Surprisingly, I find myself in complete agreement with NIN74.

It'd be nice to see the personal attacks/diatribes end. Perhaps BOTH sides could simply ignore the baiting and let it (finally) end.

I personally do not like the dynamic loudness in the Audyssey or the Tact gear. Maybe my ears have gotten used to how my system sounds at various volume levels.

Speaker/driver correction and even more so PEQ for room anomalies below 200hz, that's another matter.

Audioguy ... would be nice to see the attacks end on ALL sides.

I've learned quite a bit from John's posts, as well as our Physicist's

I generally agree with you Bruce.

Below is to the discussion as a whole,

The problem here is that it's easy for those with hard-line/extreme opinions to have lots of answers (i.e. what a speaker needs to do or how it should operate). I'm much more a realist than an idealist; probably to my detriment in the marketing department, but I sleep well. :rolleyes:

Things get easy if you think you can describe a sufficient number of clear constraints to make a great sounding speaker. Ask 10 different designers their ideal behavior of a *real* speaker, and you will get 10 different answers and orders of priorities. We're so far from anything that resembles a "perfect" reproduction with any real acoustic devices at desired playback levels that this is inevitable.

Most all of the decisions in speaker design could be boiled down to simulation with a set of initial and target values, along with operational constraints. Unless you are using the identical formula and approach for all of your designs, it generally isn't worth the hassle of setting up something this complete, as it's quicker to just target certain behaviors per design.

When I design a new speaker I generally start with a reasonable approximation of the entire system, down to the crossover type and expected radiation characteristics before anything is constructed or tested. Once a target looks both desirable and plausible to build, then proofs/prototypes are built and are correlated to the model, where the model is adjusted for better correlation with reality. While there is generally some listening/pre-screening of raw parts for misbehavior, only after the prototype is starting to close in on the target measurement and behavior do I start listening for things that might have not been accounted for, and to confirm the target actually sounds pleasing. No adjustments are done without measurement and quantification, although the decision to make a adjustments is often driven by subjective observation and further investigative measurement, searching for further correlation.

So many seem to be desperately clamoring for conclusions of why they are hearing what they hear, often leading to confusion of coincidence with causality.

While the above might not seem terribly relevant, it is. The question should not be what could/can we do with DSP, but rather what is needed to improve the subjective quality of our speakers? As has already been said/implied, chasing any one characteristic or behavior to the extreme will usually lead to inadequacies elsewhere.

Back to the usual volleys... :rolleyes:

http://www.htguide.com/forum/images/smilies/icon_tennis.gif

Sorry, I don't believe you at all. If you did a blindtest between speaker, passive and digital active speakers, I can put a big sum och cash that you will NOT get 100% right.

How about 60%? That's statistically better than guessing. But what I'd want to hear is a passive speaker, then the same speaker DEQXed. I'd bet I can do that more like 80-90%. And how much cash are we talking?


Again, you THINK that digital active crossover is the best and if the speaker don't work, it must be something else. The problem is that you have made up your mind that "this is the best" and will stand by it even when it is not a logical choose.

No, not really. When I listen to a Meridian speaker, I honestly feel like all I can hear are the drivers. Not the crossover, not the cabinet. When I hear many other speakers, there's more color there than the drivers alone should reproduce. I just have a LOT of experience with DSP speakers and doing tons of A/B testing compared to passive speakers. How many DSP speakers have you owned?

Besides, it could just be the multi-amped active design, so I may not be able to tell the difference between an analog crossover and a digital crossover, though DEQX does far more that than.

The question should not be what could/can we do with DSP, but rather what is needed to improve the subjective quality of our speakers? As has already been said/implied, chasing any one characteristic or behavior to the extreme will usually lead to inadequacies elsewhere.

Very true, but of course, digital just makes it easier (though more expensive). I was thinking about a design I have for a 5-way speaker and it would be a massive hassle to build it with passive crossovers, but it would be far easier with digital crossovers, if I can find one that will do 5-way.

Very true, but of course, digital just makes it easier (though more expensive). I was thinking about a design I have for a 5-way speaker and it would be a massive hassle to build it with passive crossovers, but it would be far easier with digital crossovers, if I can find one that will do 5-way.

There are plenty of off the shelf means to execute 10-12 way or more loudspeakers if desired. The question is then if they are up to signal quality and have low enough noise floor (slightly different than dynamic range) to not bring in other compromises in a design. "Good enough" will depend greatly on the context of all parts in the system, and is hardly an absolute.

Digital input for 2ch playback is readily available, but the copyright protection on multi-channel signals makes things much more difficult. Plenty of audio over Ethernet solutions exist, but they are not readily able to directly pass digital signals from say an HDMI format.

I am a big fan of active systems executed with DSP, but as with most any tool, execution and use is MUCH more important than the tool.

There are plenty of off the shelf means to execute 10-12 way or more loudspeakers if desired. The question is then if they are up to signal quality and have low enough noise floor (slightly different than dynamic range) to not bring in other compromises in a design. "Good enough" will depend greatly on the context of all parts in the system, and is hardly an absolute.

Well, if you know of a *good* high-bit one with digital inputs and 5-way capability (I don't see the point beyond that), preferably somewhat modular, I'm all ears!

Digital input for 2ch playback is readily available, but the copyright protection on multi-channel signals makes things much more difficult. Plenty of audio over Ethernet solutions exist, but they are not readily able to directly pass digital signals from say an HDMI format.

Yeah, that's the frustrating thing, it's almost all proprietary closed systems to do multi-channel. Although, if you tweaked the gains, you could get pretty close with analog ins, especially with theater where there is some standardization of volume.

I am a big fan of active systems executed with DSP, but as with most any tool, execution and use is MUCH more important than the tool.

I agree, but it sure is promising from the few systems that are available.

"How about 60%? That's statistically better than guessing."

Blind tests aren't passed simply by the percentage correct, they are passed by the possibility of the results occuring by chance being below some pre-determined percentage. Typically that is the 95% confidence test.. meaning there was less then a 5% chance that the results happened by chance. That is considered a pass in most ABX tests I have seen.

This sounds like the same thing as 60% correct but it isn't. Consider someone saying they scored 100% correct on an ABX test. Is that better or worse then someone that scored only 60% correct on an ABX test?

The correct answer if you don't have enough information.

If the person scored 100% correct only had a single trial a score of 100% would happen by chance 50% the time. If the person that scored 60% correct did that on 100 trials that would happen by chance a little less then 3% of the time. In that example the person scoring 60% passed the trial the person scoring 100% did not.

Likewise scoring 60% correct on 10 trials would occur by random chance about 37% of the time... that is not a passed test.

Shawn

"Well, if you know of a *good* high-bit one with digital inputs and 5-way capability (I don't see the point beyond that), preferably somewhat modular, I'm all ears!"

A pair of Behringers would give you digital in and up to a single 6 way speaker for each crossover. If you want to avoid their analog stage you can mod them for 3x S/PDIF output easily. Especially handy if you go to class D amps with digital inputs.

Shawn

I was thinking about a design I have for a 5-way speaker and it would be a massive hassle to build it with passive crossovers, but it would be far easier with digital crossovers, if I can find one that will do 5-way.

I posted this earlier http://www.xta.uk.com/products-series4.html but maybe you didn't look into it because it isn't made by DEQX. The DP448 could be used for a single up to 8-way speaker, or a pair of 4-ways.

"How about 60%? That's statistically better than guessing."

Blind tests aren't passed simply by the percentage correct, they are passed by the possibility of the results occuring by chance being below some pre-determined percentage. Typically that is the 95% confidence test.. meaning there was less then a 5% chance that the results happened by chance. That is considered a pass in most ABX tests I have seen.

Sure, but I can't predict whether I'd do 100% or not. It might be unbelievably easy or I might make a mistake or two. It depends on how many variables. If the only variable is passive versus active crossover, it should be pretty easy to score higher.

I posted this earlier http://www.xta.uk.com/products-series4.html but maybe you didn't look into it because it isn't made by DEQX. The DP448 could be used for a single up to 8-way speaker, or a pair of 4-ways.

Looks cool, though I am kind of looking more for an OEM type solution. DEQX says it's up to a new OEM system, but specifics aren't available. I just like DEQX because i know it so well, but am certainly open to other things.

Trinnov now has per channel digital crossovers, bass management, and PEQ. I think but am not sure there are up to 24 outputs.

You can see screen shots on their website

You don't have to use their room processing if you don't want to.

I know it can easily do stereo five ways.

Modular.

Multiple inputs, analog and digital, and multiple presets.

Lacks surround processing, which would have to be done upstream.

I have not heard it, but am strongly considering it.

Trinnov now has per channel digital crossovers, bass management, and PEQ. I think but am not sure there are up to 24 outputs.

You can see screen shots on their website

You don't have to use their room processing if you don't want to.

I know it can easily do stereo five ways.

Modular.

Multiple inputs, analog and digital, and multiple presets.

Lacks surround processing, which would have to be done upstream.

I have not heard it, but am strongly considering it.

The Trinnov processor is on my radar as well. I know a few who will be using it in the future and await their impressions. It sounds quite promising.

Looks cool, though I am kind of looking more for an OEM type solution. DEQX says it's up to a new OEM system, but specifics aren't available. I just like DEQX because i know it so well, but am certainly open to other things.

For the record, while we got some much improved results with lots of playing, the DEQX absolutely drove me nuts in use as it was very limited in what you could make it do to combat out of band issues or in making adjustments in the driver overlap/crossover region. It is able to give you good results very quickly, and will work better with more simplistic driver configurations.

For the record, while we got some much improved results with lots of playing, the DEQX absolutely drove me nuts in use as it was very limited in what you could make it do to combat out of band issues or in making adjustments in the driver overlap/crossover region. It is able to give you good results very quickly, and will work better with more simplistic driver configurations.

I know they don't give you anything really besides symmetrical crossovers, but basically that is because they optimize the impulse response first, in theory making that unnecessary. Well, you know, "in theory".

Two questions, though - what specifically would you want it to do to compbat out of band issues aside from steep crossovers and impulse response correction and secondly, what do you mean by "more simplistic driver configurations"?

Trinnov now has per channel digital crossovers, bass management, and PEQ. I think but am not sure there are up to 24 outputs.

I know it can easily do stereo five ways.

Well, they say they can do up to 4-way and that's actually okay. I have in mind a 5-way design, but it's a little overkill ;)

...what do you mean by "more simplistic driver configurations"?
Perhaps a two or three way instead of a four or five way.

Perhaps a two or three way instead of a four or five way.

It's a 3-way crossover, so that's a bit obvious. I am wondering if he's referring to the kinds of drivers or number of drivers, monopole vs dipole, etc.

It's a 3-way crossover, so that's a bit obvious. I am wondering if he's referring to the kinds of drivers or number of drivers, monopole vs dipole, etc.
I've read through this thread and frankly have no idea why this is in the Ultra Hi-End HT Gear ($20,000+) forum; it seems to me this should be over in the DIY Speakers and Subs forum, or at least in the Speakers forum. Maybe the moderator needs to move it where it is more relevant.

Because DSP is the way of the future and because many of them are well above $20K. At least this thread has *some* gear over $20K. Most threads here don't have anything over $10K, the new Arcam thread, for instance. Maybe add a few zeros to your post count and then criticize.

Because DSP is the way of the future and because many of them are well above $20K. At least this thread has *some* gear over $20K. Most threads here don't have anything over $10K, the new Arcam thread, for instance. Maybe add a few zeros to your post count and then criticize.
It just seemed like a do it yourself speaker thread to me. Sorry, I didn't realize there was a post count requirement to participate. Are you a moderator?

It just seemed like a do it yourself speaker thread to me. Sorry, I didn't realize there was a post count requirement to participate. Are you a moderator?

No, but it strikes me as odd that you seem to be here only to create problems for the thread, rather than 'participate'. And it seems maybe you are someone that was tossed off AVS and reborn under a new name (only 4 posts, all on one thread, mostly critical? C'mon). But either way, I did start the thread and it is largely about manufactured DSP speakers, though you can obviously roll your own if no one is building what you are seeking.

No, but it strikes me as odd that you seem to be here only to create problems for the thread, rather than 'participate'. And it seems maybe you are someone that was tossed off AVS and reborn under a new name (only 4 posts, all on one thread, mostly critical? C'mon). But either way, I did start the thread and it is largely about DSP speakers, though you can obviously roll your own if no one is building what you are seeking.
Well, this is quite a welcome.

I've read through this thread and frankly have no idea why this is in the Ultra Hi-End HT Gear ($20,000+) forum; it seems to me this should be over in the DIY Speakers and Subs forum, or at least in the Speakers forum. Maybe the moderator needs to move it where it is more relevant.

A number of digital active speakers are up there in price. Klein + Hummel o500c is $18k each. Times 7 = $126k msrp. The Legend Tikandi that Alimentall is so fond of is something like $25k/pair; times 3.5 = $87k. The standalone crossover I linked to is by itself only $5800, but put a pair of similar ones into a package with a pair of Dynaudio M4Us and 4 Chord amps, and you're at $62k list for a pair of "digital active speakers"; times 3.5 = $217k http://www.proaudiodesign.com/searchresults.php?Mfg=Dynaudio%2FMunro&advsearch=1

Well, this is quite a welcome.

Well, you made it to my 'ignore' list in a "flash", pardon the pun.

A number of digital active speakers are up there in price. Klein + Hummel o500c is $18k each. Times 7 = $126k msrp. The Legend Tikandi that Alimentall is so fond of is something like $25k/pair; times 3.5 = $87k. The standalone crossover I linked to is by itself only $5800, but put a pair of similar ones into a package with a pair of Dynaudio M4Us and 4 Chord amps, and you're at $62k list for a pair of "digital active speakers"; times 3.5 = $217k http://www.proaudiodesign.com/searchresults.php?Mfg=Dynaudio%2FMunro&advsearch=1
Thanks for the clarification. It makes more sense now.

It is surprising to see even NIN74 disagreeing with Alimentall. Surprisingly, I find myself in complete agreement with NIN74.

it seems to me this should be over in the DIY Speakers and Subs forum, or at least in the Speakers forum.

It is surprising to see someone whose first post was only yesterday writing things such as the above, as the comments seem to indicate a certain familiarity with NIN74's and Alimentall's views, and the structure of the AVS forum. Chances are, you've actually been around these parts for quite awhile, but only the name "Barry Allen" is what is new.

It is surprising to see someone whose first post was only yesterday writing things such as the above, as the comments seem to indicate a certain familiarity with NIN74's and Alimentall's views, and the structure of the AVS forum.
It doesn't take long to become familiar with NIN74's and Alimentall's views. They litter the forum and unfortunately are such that they cannot be overlooked. About ten posts into any given thread, patently untenable claims are made, the contention begins, denial ensues, the thread is derailed and everyone becomes so exasperated the thread dies or is finally put out of its misery by the moderator. It really does a disservice to others to continue to allow them to ruin what could be a terrific forum. But I can see that I am not welcome here so I will move on. Yet another participant is run off by the demagogues. Undoubtedly I will be banned from the thread and this post deleted for speaking the truth.

It doesn't take long to become familiar with NIN74's and Alimentall's views. They litter the forum and unfortunately are such that they cannot be overlooked. About ten posts into any given thread, patently untenable claims are made, the contention begins, denial ensues, the thread is derailed and everyone becomes so exasperated the thread dies or is finally put out of its misery by the moderator. It really does a disservice to others to continue to allow them to ruin what could be a terrific forum. But I can see that I am not welcome here so I will move on. Yet another participant is run off by the demagogues. Undoubtedly I will be banned from the thread and this post deleted for speaking the truth.

Well, since you seem to enjoy playing cop and are saying you'll be leaving, you can go over to the Arcam thread that Alimentall mentioned and tell them that since the unit is under $20k, they should move over to another part of AVS.

I don't care for Alimentall's style, either (and in fact I had the distinct privilege of being on his ignore list for a time), but I think that the view you express above is somewhat out of line as it pertains to this thread, because it is Alimentall's thread. Do you feel he has derailed his own thread? I don't. It is true that the more recent posts are somewhat about standalone digital active crossovers, which could be used DIY, but I really don't consider that a derailment from the thread topic, anymore than a discussion of the merits of, say, coaxial drivers would be in a thread that had the titile "KEF Reference speakers".

EDIT: The funny thing about your attitude is that, if he posted stuff about DEQX and digital active speakers on the Magico V5 thread or the Kharma Grand Exquisite thread (which he has), you would be telling him (perhaps justly) to "go start your own thread." Well, he has done that. And yet you can't stop with the criticism?

Barry, if you get banned, it'll be because your IP matches up with another nick or two :D

How about 60%? That's statistically better than guessing. But what I'd want to hear is a passive speaker, then the same speaker DEQXed. I'd bet I can do that more like 80-90%. And how much cash are we talking?

60% gives nothing.



No, not really. When I listen to a Meridian speaker, I honestly feel like all I can hear are the drivers. Not the crossover, not the cabinet. When I hear many other speakers, there's more color there than the drivers alone should reproduce. I just have a LOT of experience with DSP speakers and doing tons of A/B testing compared to passive speakers. How many DSP speakers have you owned?


Non! I have listen to Meridian and maybe some other, but the real question is, why you believe that DSP speaker is so much better. Speakers are not better than all its sums.

60% gives nothing.

Give me specifics. What speakers am I listening to? How much money? Who's doing the switching, etc, etc, etc. I need to know before I decide whether to take your money. Throw Xd in as the DSP speaker and I *definitely* will take all your money.

Non! I have listen to Meridian and maybe some other, but the real question is, why you believe that DSP speaker is so much better. Speakers are not better than all its sums.

Exactly. All passive speakers are somewhat crippled and simply can't surmount this. DSP crossovers don't instantly make the speaker better than all other speakers, it makes it better than it would be without it. Actually, much of which is because of the multi-amped design. I would not use the drivers that Meridian uses as I think there are much better drivers, but they still do micro dynamics much better than speakers I've heard with much better drivers and they don't fatigue even at high volumes.

For the record, while we got some much improved results with lots of playing, the DEQX absolutely drove me nuts in use as it was very limited in what you could make it do to combat out of band issues or in making adjustments in the driver overlap/crossover region. It is able to give you good results very quickly, and will work better with more simplistic driver configurations.

I know they don't give you anything really besides symmetrical crossovers, but basically that is because they optimize the impulse response first, in theory making that unnecessary. Well, you know, "in theory".

Two questions, though - what specifically would you want it to do to compbat out of band issues aside from steep crossovers and impulse response correction and secondly, what do you mean by "more simplistic driver configurations"?

Not answering for Mark Seaton, but since he helped me with my DEQX in a two way line array setup augmented with a pair of mono subs, I'd suggest the following would be nice additions, in priority order ...

(1) The ability to apply PEQ per channel and per driver. Right now you can only do manual PEQ overall for both channels for all drivers. In my case I would have liked to have damped down a "sibilance" in the tweeter array that was below the frequency that the midrange centered around.

(2) The ability to use different measurement sets for the various drivers, and, to combine measurement sets for the drivers (more of an "averaging" feature.)

(3) The ability to have non symmetrical slopes between the mids and tweets. (You can do this between the mids and subs already though.)

Not answering for Mark Seaton, but since he helped me with my DEQX in a two way line array setup augmented with a pair of mono subs, I'd suggest the following would be nice additions, in priority order ...

(1) The ability to apply PEQ per channel and per driver. Right now you can only do manual PEQ overall for both channels for all drivers. In my case I would have liked to have damped down a "sibilance" in the tweeter array that was below the frequency that the midrange centered around.

(2) The ability to use different measurement sets for the various drivers, and, to combine measurement sets for the drivers (more of an "averaging" feature.)

(3) The ability to have non symmetrical slopes between the mids and tweets. (You can do this between the mids and subs already though.)

You have custom line arrays, correct?

Yes, Rick Craig built me some rosewood finished arrays with 8 Accuton midwoofers per side and 8 Fountek ribbons per side, both in sealed cabinets.

3db down at 90hz crossing over to a pair of monster subs from Mark Seaton.

Very true, but of course, digital just makes it easier (though more expensive). I was thinking about a design I have for a 5-way speaker and it would be a massive hassle to build it with passive crossovers, but it would be far easier with digital crossovers, if I can find one that will do 5-way.

BTW Linn has an active 5-way, the Klimax 350A; I think the crossover is analog. Even the active center, the 340A, is 5-way, which I have never heard of before. Kind of pricey, though.

Exactly. All passive speakers are somewhat crippled and simply can't surmount this.


Have you hear EVERY passive speakers on the earth? Could you provide ANY proof for this other that "I think so, therefore it is so"?

Have you hear EVERY passive speakers on the earth? Could you provide ANY proof for this other that "I think so, therefore it is so"?

I have legitimately heard *hundreds* of loudspeakers, maybe even over 1000.

Besides, it actually make sense that active systems have greater macro/micro dynamics. Can you prove the opposite? How does pushing the signal through capacitors, inductors, resistors make the sound even potentially as good? If these parts were sonically transparent, they wouldn't even function.

BTW Linn has an active 5-way, the Klimax 350A; I think the crossover is analog. Even the active center, the 340A, is 5-way, which I have never heard of before. Kind of pricey, though.

Yeah, they force you into very overpriced, cheaply made amps with drop in analog crossover cards (seriously, $3300 for an entry level amp that probably has $100-$200 in parts? That was the same retail as NHT's Xd amp with 4 amp channels and DEQX!) We had a customer who had a full 'activ' Espek system and he tried DEQX and his wife immediately said 'this stays, no need to go back' so we sold his Linn amps. Then he swapped out his Espeks for the Xd speakers as they were designed for DEQX and we sold his Espeks.

Yes, Rick Craig built me some rosewood finished arrays with 8 Accuton midwoofers per side and 8 Fountek ribbons per side, both in sealed cabinets.

3db down at 90hz crossing over to a pair of monster subs from Mark Seaton.

Are you using a fairly mild, high frequency slope then? And were you getting sibilance before the DEQX? I just wonder if the DEQX is over correcting (ribbons don't behave pistonically, so DEQX could be adding some artifacts trying to over correct), unless the sibilance wasn't always there. It can also pick up anomalies from multiple tweeters and try to fix the unfixable. So you would want to smooth the correction quite a bit, I should think. Just curious what settings Mark ended up with and why. I never really attempted an array because I don't have any, but I think I mentioned that they gain less from correction and steep crossovers than small point source speakers, though a bit of FR correction can go a long way.

I have legitimately heard *hundreds* of loudspeakers, maybe even over 1000.

Besides, it actually make sense that active systems have greater macro/micro dynamics. Can you prove the opposite? How does pushing the signal through capacitors, inductors, resistors make the sound even potentially as good? If these parts were sonically transparent, they wouldn't even function.

Mr Alimentall

I use active routing because I find it interesting and because several Studio PRO Monitors use it and that the Behringer and DIY are within my meager budget, not because I have heard limitation in passive speakers, aside that they for the most part don't seem to ever play loud enough :). I am studying EE and became interested interested in signal processing. Even when we choose to to digitally process our signals, to hear them we ultimately have to make them analog and there they will go through Resistors capacitors and other impedance. Also if LRC elements behave perfectly then they will indeed function and function perfectly. There are losses involved in Passive Crossovers that are mitigated in Active crossovers either analog or Digital. I do not know if that will help with the reproduction of "micro" or "macro" dynamics .. Are there scientific studies on the relative values of Active versus Passive Crossovers that have reached similar conclusions? Any URL or references would help.

http://www.mackie.com/products/mackietechnology/Active_vs_Passive.html

http://www.genelec.fi/ht/tuotetuki/active-passive/

http://www.tnt-audio.com/casse/active_speakers_intro1_e.html

http://www.hometheaterhifi.com/volume_9_4/feature-article-active-speakers-12-2002.html

http://fulmonn.blogter.hu/299319/biamp_vs_passive_crossover

http://www.enjoythemusic.com/Magazine/manufacture/0403/

Are you using a fairly mild, high frequency slope then? And were you getting sibilance before the DEQX? I just wonder if the DEQX is over correcting (ribbons don't behave pistonically, so DEQX could be adding some artifacts trying to over correct), unless the sibilance wasn't always there. It can also pick up anomalies from multiple tweeters and try to fix the unfixable. So you would want to smooth the correction quite a bit, I should think. Just curious what settings Mark ended up with and why. I never really attempted an array because I don't have any, but I think I mentioned that they gain less from correction and steep crossovers than small point source speakers, though a bit of FR correction can go a long way.

Crossover between mids and ribbons is at 1900hz at 48db/octave. We used maximum smoothing as recommended by DEQX. We took quite a few measurments, at various heights, distances, and axis deltas before choosing a measurement set that had nice characterstics. (96 db per ocatave was just about the same sonically as 48db/octave.) We also varied the amount of correction that we allowed the DEQX to do quite a bit across the frequency band. "Playing" with that allowed us to establish more/less correction around the crossover point.

For the Accutons to the subs we used an asymmetric slope so that the mechanical roll off from the Accutons, when added to the slope of the crossover, equaled the slope that we used on the subs themselves. We also overlapped the crossover points a bit, with the subs coming in around 20hz higher than the mids were falling off. (There's a separate QSC DSP30 that we used for the subs' low pass filter and PEQ.)

The ribbon dipole HAS to have a "figure-8 like" dispersion due to the physical symmetry.
The dipole looks the same front and back except that the two side radiate with opposite
phase. If the direct radiation doesn't have a null at the side - then which side wins?


If the driver does not have enough horizontal dispersion for the front and back wavefronts to meet, then there is no dipolar cancellation. Look at the wavelengths involved, and the horizontal size of the radiators. The radiators are often as large or larger than the wavelengths, which means they beam and have narrow dispersion, therefore no dipolar pattern.

This is borne out not only by theory but by actual measurements.

They approach looking infinitely long at much lesser lengths. You need to a get a good
book on wave theory which includes expansions in spherical harmonics.


I understand spherical harmonics well, but I don't understand what you mean by "looking infinitely long at much lesser lengths." What matters is the benefit that a long line array gives you. Looking at the vertical dispersion patterns of the panel speakers being discussed, I think you are giving them way more credit than they deserve.


The room response is separated in time. I'm talking about how the cymbal sounds when
it is first struck. The room response doesn't enter into that - because the sound waves
haven't had a chance to hit the room boundaries.


Without knowing the geometry of the recording venue, there is no way you can say that room response has nothing to do with it. For example, you don't know that there is a closer reflecting surface than the mic.

The drummer isn't going to be able to appreciably affect the dynamics of the response
of the cymbal.


That's a mighty poor drummer.

I don't know about the others - but I sure can hear the difference. I think it has to do with knowing what to listen for.


Are you willing to try the Keith Howard test CD, and see if you can do better than the audio reviewers?

--Andre

If the driver does not have enough horizontal dispersion for the front and back wavefronts to meet, then there is no dipolar cancellation. Look at the wavelengths involved, and the horizontal size of the radiators. The radiators are often as large or larger than the wavelengths, which means they beam and have narrow dispersion, therefore no dipolar pattern.

Andre! If the speaker has little to no signal off to the sides, it still has a figure 8 pattern! The dispersion doesn't matter, wide or narrow because as long as it is equal and opposite, you will always get a figure 8 because you will always have essentially perfect cancellation where they meet, regardless of whether it's 10dB down or 50dB down. I'm just sayin' and you know how rarely I agree with Greg.

For the Accutons to the subs we used an asymmetric slope so that the mechanical roll off from the Accutons, when added to the slope of the crossover, equaled the slope that we used on the subs themselves. We also overlapped the crossover points a bit, with the subs coming in around 20hz higher than the mids were falling off. (There's a separate QSC DSP30 that we used for the subs' low pass filter and PEQ.)

Keep in mind that, in essence, the DEQX will use the natural rolloff of the speaker in its calculations. If the speaker is rolling off at 12dB/octave, it will first flatten it, then it will add in, say, the 48dB/octave crossover. When you sub the 12dB/octave compensation, you end up with, in essence, a 36dB/octave electric crossover with a 12dB/octave acoustic rolloff. So, if one of the speakers is rolling off naturally, DEQX is using an asymmetric electrical crossover, but with a symmetric result.

I have legitimately heard *hundreds* of loudspeakers, maybe even over 1000.

Besides, it actually make sense that active systems have greater macro/micro dynamics. Can you prove the opposite? How does pushing the signal through capacitors, inductors, resistors make the sound even potentially as good? If these parts were sonically transparent, they wouldn't even function.


No proof at all, sorry.
Prove? Well, come with your NHT speakers so can we compare them to my speakers.

Crossover between mids and ribbons is at 1900hz at 48db/octave. We used maximum smoothing as recommended by DEQX. We took quite a few measurments, at various heights, distances, and axis deltas before choosing a measurement set that had nice characterstics. (96 db per ocatave was just about the same sonically as 48db/octave.) We also varied the amount of correction that we allowed the DEQX to do quite a bit across the frequency band. "Playing" with that allowed us to establish more/less correction around the crossover point.

Sounds like about what I would do, but can't figure out why you'd get any sibilance unless maybe the ribbons don't like being crossed over so low? But with so many, they shouldn't really be pushing that much. Is the DEQX EQing them down low? If the ribbons are starting to roll off at, say, 2500Hz, that would cause issues. Just spitballing here. You don't want DEQX to EQ the driver at the bottom end of its used range. You want to insert the crossover at a point above that.

No proof at all, sorry.
Prove? Well, come with your NHT speakers so can we compare them to my speakers.

If you really want proof of an active speaker's superiority, you need to provide two identical speakers, one with stock crossovers, the other with a digital crossover, then A/B them. I've done this with DEQX (well, a before, after) and there's no question the 'after' is better. But I could pick Xds out of a lineup probably 100% of the time. Just tell me what you want to prove/disprove and how much money you want to put up so I can see if it's worth the plane flight. Probably not, but maybe. Maybe if you actually owned some DSP speakers, you'd understand.

Also, I provide 6 or 7 links that assert the superiority of DSP crossovers and multi-amplification (and can easily find more). Can you provide *one* that asserts that passive is better than DSP active? Just one.

Keep in mind that, in essence, the DEQX will use the natural rolloff of the speaker in its calculations. If the speaker is rolling off at 12dB/octave, it will first flatten it, then it will add in, say, the 48dB/octave crossover. When you sub the 12dB/octave compensation, you end up with, in essence, a 36dB/octave electric crossover with a 12dB/octave acoustic rolloff. So, if one of the speakers is rolling off naturally, DEQX is using an asymmetric electrical crossover, but with a symmetric result.

Not in my case ... I don't use the DEQX for correction between the mids and subs. I use the manual roll off in the DEQX for the high pass on the midranges (12 db mechanical plus 12db electrical), and I use an outboard PEQ crossover for the subs. All the slopes / interfaces are well behaved and were separately measured.

If you really want proof of an active speaker's superiority, you need to provide two identical speakers, one with stock crossovers, the other with a digital crossover, then A/B them. I've done this with DEQX (well, a before, after) and there's no question the 'after' is better.

This is exactly what I did. My line arrays have terrific passive crossovers built in, and, were wired so that they could be bypassed with my DEQX. The amps are identical in both situations. The actively crossed configuration sounds a lot, not subtly, better.

There's no guarantee that you'd get the same results with other speakers, and I don't represent my "sample of one" as being representative.

Still, it was big enough that all the new speakers I've commissioned will have crossovers that can be bypassed.

John,

I think I found a pair of B&Ws that you might actually like!

http://www.avsforum.com/avs-vb/showthread.php?t=1125102

I like all the B&Ws that don't have kevlar! Mostly back when B&W was a speaker company, not a marketing company :)

Andre! If the speaker has little to no signal off to the sides, it still has a figure 8 pattern!

Yes, there will be little sound to the sides, but it will not be a dipolar pattern (ie. figure-8). It will be closer to putting two out-of-phase narrow cardioids back to back.

--Andre

Yes, there will be little sound to the sides, but it will not be a dipolar pattern (ie. figure-8). It will be closer to putting two out-of-phase narrow cardioids back to back.

Mmmmmm, I think you're praying on semantics to save you on that one, but it doesn't matter because as long as you have cancellation to the side, whether it's strong or weak, you end up with a signal approaching zero to the sides. That makes a figure 8. It doesn't matter the shape of the lobes, it will still be a figure 8. Maybe a fat 8 or a narrow 8, but it's an 8. 75dB-75dB=0. 25dB-25dB=0. 5dB-5dB still=0, therefore it is a dipole figure 8. It pains me to say this, but that's just the way it is. A cartoid has far more energy off to the side than a dipole.

BTW, I found this 4-way DSP crossover w/up to 48dB/octave slopes -

http://www.ashly.com/protea424c.html

That's a nice unit, I have one. The amount of control is amazing, including eq/notch filter for each separate output, perfect for my Bohlender-Graebener planars. Hook it up with a serial cable to your HTPC and control the unit on the nice big front projector screen, lotsa fun. :D

The only drawback is a tiny 1" diameter cooling fan that screams like a jet engine.

I also have this fine analog quad-amp Ashly xover: http://www.fullcompass.com/product_image.php?imageid=220

Electronic crossovers have been a way of life for me for going on 30 years now.. as previously posted, it's the only way to easily mix/match/experiment using different drivers.

Mmmmmm, I think you're praying on semantics to save you on that one, but it doesn't matter because as long as you have cancellation to the side, whether it's strong or weak, you end up with a signal approaching zero to the sides. That makes a figure 8. It doesn't matter the shape of the lobes, it will still be a figure 8. Maybe a fat 8 or a narrow 8, but it's an 8. 75dB-75dB=0. 25dB-25dB=0. 5dB-5dB still=0, therefore it is a dipole figure 8. It pains me to say this, but that's just the way it is. A cartoid has far more energy off to the side than a dipole.
Actually, all figure eights are dipole patterns, but not all dipole patterns are figure eights. The terms are not synonymous.

Here's an interesting studio speaker, though I don't understand the point of soft dome mids and tweeters when you have steep crossovers at your beck and call. I guess this is one of Andreas' favorites?

http://www.bhphotovideo.com/images/largeimages/574050.jpg

If you really want proof of an active speaker's superiority, you need to provide two identical speakers, one with stock crossovers, the other with a digital crossover, then A/B them. I've done this with DEQX (well, a before, after) and there's no question the 'after' is better. But I could pick Xds out of a lineup probably 100% of the time. Just tell me what you want to prove/disprove and how much money you want to put up so I can see if it's worth the plane flight. Probably not, but maybe. Maybe if you actually owned some DSP speakers, you'd understand.


Sorry, you just sound like a fanatic fanboy. You have still not given any proof for what you are saying, just that a NHT speaker that almost nobody wanted, is better than most others.

Sorry, you just sound like a fanatic fanboy. You have still not given any proof for what you are saying, just that a NHT speaker that almost nobody wanted, is better than most others.

And what speakers you have? The NHT had a combination of sound qualities simply not available in most any, *if* any, high end speaker. Very wide, smooth dispersion, flat 20Hz-20kHz (with crossover update), virtually perfect point source radiation and coherence, very high resolution, virtually non-existent fatigue factor, very high output, small form factor, huge soundstaging, pin point imaging, extremely flat/accurate/precise bass. Name another speaker that can do it. Just one.

Sorry, you just sound like a fanatic fanboy. You have still not given any proof for what you are saying, just that a NHT speaker that almost nobody wanted, is better than most others.

Nin74 ... not intending to get into a debate about the NHTs, ...

I have heard the exact same speaker in the exact same room with the exact same placement, sources, amps, etc. with and without an active DEQX crossover. (These were bespoke line arrays with bypassable passive crossovers.) The actively crossed units were/are materially better.

An observation of quantity one.

And to put a finer point on it, line arrays probably benefit least from DEQX because they have strengths that DEQX can't improve upon much (dynamic range, low motor distortion) and some weaknesses that DEQX can't completely correct (cone interference patterns). BUT......I've never heard a speaker that doesn't or wouldn't benefit greatly from DEQX.

And what speakers you have? The NHT had a combination of sound qualities simply not available in most any, *if* any, high end speaker. Very wide, smooth dispersion, flat 20Hz-20kHz (with crossover update), virtually perfect point source radiation and coherence, very high resolution, virtually non-existent fatigue factor, very high output, small form factor, huge soundstaging, pin point imaging, extremely flat/accurate/precise bass. Name another speaker that can do it. Just one.
Would you give the NHT Xd and DEQX a rest? You've already beaten us senseless with your endless posts about them.

And what speakers you have? The NHT had a combination of sound qualities simply not available in most any, *if* any, high end speaker. Very wide, smooth dispersion, flat 20Hz-20kHz (with crossover update), virtually perfect point source radiation and coherence, very high resolution, virtually non-existent fatigue factor, very high output, small form factor, huge soundstaging, pin point imaging, extremely flat/accurate/precise bass. Name another speaker that can do it. Just one.


I would say Ino audio would do it. I one of his speaker and I have not heard ANY speaker that are even close are correct as those. And then I have heard many of those "high-end" speakers that many are so fond about.

Have measurements?

Edit - can you do better than a just beyond DIY brand sold only in Sweden?

I believe this belongs in this thread so here goes ...

How good are Meridian speakers for a 7.1 HT?

e.g. The DSP8000 is Meridian's flagship loudspeaker. How good is a front array of a DSP8000 compared to a front array of any other passive speaker with amplification in the same price vicinity?

Meridian just flat out rocks for HT. It *is* expensive, no doubt. Meridian isn't ruthlessly resolving, which kinda sucks on typical movie stuff. BUT, it is incredibly dynamic, both in dealing with very loud transients and with very soft sounds normally buried by, I suspect, the passive crossover in most speakers. It is also shockingly reliable for equipment that is this sophisticated (we had far more problems with NHT's Xd than we've ever had with Meridian). Very tweakable as well. If I were planning on spending $100K+ on HT gear, I'd almost certainly go Meridian because of what the digital active design does for the sound. Value? Forget about that, that isn't the purpose. And while the DSP7200s we just did for a customer are $35k with amplification, I find them to be more enjoyable than the $20K speakers I've heard that pound you with 'resolution' or some other kind of flavor.

dealing with very loud transients and with very soft sounds normally buried by, I suspect, the passive crossover in most speakers

Can you point to any sources that would corroborate this theory of yours?

I already did several posts back. Lack of dynamic compression due to lack of heat producing crossover parts is cited in several articles. Even the Revel Studio2s sound somewhat compressed and strained compared to the DSP7200s, even with more exotic drivers. When it comes to playing loud well, the DSP7200s would be up there in my choices.

Now, can you come up with any sources to refute it?

I already did several posts back. Lack of dynamic compression due to lack of heat producing crossover parts is cited in several articles. Even the Revel Studio2s sound somewhat compressed and strained compared to the DSP7200s, even with more exotic drivers. When it comes to playing loud well, the DSP7200s would be up there in my choices.

Now, can you come up with any sources to refute it?

1. You have failed to explain how a passive crossover could possibly "bury" very soft sounds. Go ahead, try to quote a specific passage.

2. If active is so much better at avoiding dynamic compression, why is the Xd so awful on the compression front? Go ahead, try to find a comparably-priced passive speaker that is the same or worse in compression above 100Hz.

3. A passive crossover does suck power compared to an active. But on the other hand, a passive crossover needs only 1 amp per pair of speakers, whereas a 3-way active speaker needs at least 3 amps per speaker pair. If the passive crossover is wasting half the power, a single 600WPC amp is still going to be alot less money than one 300WPC + one 200WPC + one 100WPC. So running a passive setup can have the same or less compression issues than an equivalently-costly active setup, assuming the same drivers. As long as the passive crossover is sufficiently robust to handle the power, compression should not be a disadvantage vs an active system.

4. Why isn't your store selling more active systems, if you are such a believer? Why not offer some Focal pro, Dynaudio pro, or at the lower end, JBL pro, Mackie, etc? Rather than various passives that you sell like PSB?

1. You have failed to explain how a passive crossover could possibly "bury" very soft sounds. Go ahead, try to quote a specific passage.

Of course I have. Passive crossovers are lossy and convert signal to heat, aside from having modulation problems and the wide variation in tolerances. You have failed to explain how a passive crossover could possibly be as transparent as a well done digital crossover.

2. If active is so much better at avoiding dynamic compression, why is the Xd so awful on the compression front? Go ahead, try to find a comparably-priced passive speaker that is the same or worse in compression above 100Hz.

The midrange driver isn't big enough to be crossed over as low as it is, though the effect is more measurable than audible. I also suspect this has to do with the spl at which they are measured and calibrated. NHT originally wanted to implement different filters at different volumes and fade between them, which would have largely if not completely fixed that issue, but it was too expensive to implement.

3. A passive crossover does suck power compared to an active. But on the other hand, a passive crossover needs only 1 amp per pair of speakers, whereas a 3-way active speaker needs at least 3 amps per speaker pair. If the passive crossover is wasting half the power, a single 600WPC amp is still going to be alot less money than one 300WPC + one 200WPC + one 100WPC. So running a passive setup can have the same or less compression issues than an equivalently-costly active setup, assuming the same drivers. As long as the passive crossover is sufficiently robust to handle the power, compression should not be a disadvantage vs an active system.

True, but you'd never get the quality of power *delivery*. But I never hear the low level resolution that I hear from a digital speaker from a passive speaker. Not even from the Revels.

4. Why isn't your store selling more active systems, if you are such a believer? Why not offer some Focal pro, Dynaudio pro, or at the lower end, JBL pro, Mackie, etc? Rather than various passives that you sell like PSB?

Hard to sell, chicken/egg. But that's why we brought back Meridian. And why I'm eyeing the idea of building my own.

Of course I have. Passive crossovers are lossy and convert signal to heat, aside from having modulation problems and the wide variation in tolerances.

No, this doesn't answer the question. Yes the passive crossover robs power, but there is no reason for it to "bury" (your word) soft passages relative to loud, which was your claim. Or are using a different-than-dictionary definition of "bury"? Don't answer, the question is rhetorical, because I give up on this line of discussion with you. I just disagree and will leave it at that.

Works for me. How many digital active speakers have you owned? So far, it seems to me that the only people who think DSP speakers don't have inherent advantages don't own any and probably haven't heard many.

Works for me. How many digital active speakers have you owned? So far, it seems to me that the only people who think DSP speakers don't have inherent advantages don't own any and probably haven't heard many.

I do think that active has some advantages and digital has some advantages, they are not the silver bullets you make them out to be, especially when one considers the cost issue. A V8 engine may be "better" to most people than a V6, but it (1) comes at a higher cost, and (2) does not in itself produce a superior vehicle...it is just one element of what might go into a superior car.

For the record, the only speakers I have owned (other than PC speakers) for the past 8 years are active, with passive crossovers. But I'm open-minded enough to recognize that limiting my choices in my next system to only active, or only active digital, is not desirable, because that part of the equation is just that - namely, PART of the equation, like the engine in a car.

On building your own active digital speakers, good luck. You said NHT spent 5 years at it, and the first attempt needed some changes. Maybe you should present the idea to some guys on the DIY section.

I do think that active has some advantages and digital has some advantages, they are not the silver bullets you make them out to be, especially when one considers the cost issue. A V8 engine may be "better" to most people than a V6, but it (1) comes at a higher cost, and (2) does not in itself produce a superior vehicle...it is just one element of what might go into a superior car.

That would be a good analogy if the V8 also had 4 wheel drive!

On building your own active digital speakers, good luck. You said NHT spent 5 years at it, and the first attempt needed some changes. Maybe you should present the idea to some guys on the DIY section.

The flaws in the Xd are simple things to correct. The powers that be wanted a sub/sat system when the market wanted a tower. The tower also fixes the midrange compression issue as you can use multiple 8" woofers and simply up the crossover frequency. IOW, simple design choices, so I know exactly what I'd do, the question is whether it would sell as it would necessarily be $20K-$30K/pr and would weigh hundreds of lbs as I envision it.

That would be a good analogy if the V8 also had 4 wheel drive!

Perhaps so because including AWD further increases cost and limits the choice of models. Active DSP speakers are kind of where V8 AWD sedans were 10 years ago. If you wanted V8 and AWD on a sedan at that time, Audi was probably the only choice in this country. If Lexus reliability or MB cachet or BMW sportiness and cachet were more important to you, or if you hated Audi's styling, you still might not buy the Audi A8, even though it had advantages in SOME areas.

Whether active DSP speakers will ever become as available as V8 AWD sedans are now....well, I'd bet against that happening, but time will tell.

Whether active DSP speakers will ever become as available as V8 AWD sedans are now....well, I'd bet against that happening, but time will tell.

It's inevitable. In fact, I dare say they might take over mass market before they take over high-end because of the increasing demand for wireless speakers and/or computer monitors. Once you make a speaker wireless, it has to be powered. Once the speaker is powered, it might as well have a DSP crossover. The transformer is typically the most expensive part of an amplifier.

It's inevitable.

That is a matter of opinion, and in my opinion, it is far from inevitable.

In fact, I dare say they might take over mass market before they take over high-end because of the increasing demand for wireless speakers and/or computer monitors. Once you make a speaker wireless, it has to be powered.

And because it is powered, it isn't really wireless...you still have a "wire" in the form of a AC power cord. So imo there isn't that much of a demand push from wireless speakers.

Once the speaker is powered, it might as well have a DSP crossover. The transformer is typically the most expensive part of an amplifier.

Another issue is that surround prepros typically don't have digital outs. You then have added cost in additional A/D D/A at the speaker level, plus some dealers and customers will feel that another A/D D/A at the speaker level will impact SQ, negating some/all of the benefit from having a digital crossover.

Anyway, projecting the future is a matter of opinion. I'll be happy to revist this in 5-10 years and see if active digital speakers are more than a niche then.

That is a matter of opinion, and in my opinion, it is far from inevitable.

Trust me, it's inevitable. Just like when people called me nuts 6 or 7 years ago for predicting 4K projectors for the home, right about, uhhhhh, now.

And because it is powered, it isn't really wireless...you still have a "wire" in the form of a AC power cord. So imo there isn't that much of a demand push from wireless speakers.

Wireless transmission. Well, I kinda sell stuff so I can tell you that one of the biggest persistent questions we get is 'do you sell wireless speakers?'. Of course, that is followed by 'do they sound good?' So we sell tons of Sonos.

Another issue is that surround prepros typically don't have digital outs. You then have added cost in additional A/D D/A at the speaker level, plus some dealers and customers will feel that another A/D D/A at the speaker level will impact SQ, negating some/all of the benefit from having a digital crossover.

There won't even *be* digital outputs. It will all run on ethernet and/or wireless. I've already talked to NAD about this possibility in the future. Cautious, but curious, so it's a start.

Anyway, projecting the future is a matter of opinion. I'll be happy to revist this in 5-10 years and see if active digital speakers are more than a niche then.

And experience. I'll be glad to put a bet on it if you like :)

As in, within 5 years, at least 10 *more* high-end speaker companies will have or will have announced a DSP speakers as their flagship, that at least 10 speaker companies will offer wireless IP speakers and that at least one or more will be available in Best Buy. And another $100 that by CES 2019 approximately half of all new speakers over $2500/pr are DSP active speakers. How's that? ;)

As in, within 5 years, at least 10 *more* high-end speaker companies will have or will have announced a DSP speakers as their flagship

Possibly 10 will start shipping, but how many of those will discountinue their product within 3-4 years of initial shipment, as NHT did? You forget that I own Paradigm Reference Actives myself. While not DSP, it is telling that, despite GLOWING reviews, the product line was discontinued.

$100 that by CES 2019 approximately half of all new speakers over $2500/pr are DSP active speakers. How's that? ;)

I would go farther than that. If you're willing to employ an independent escrow agency, I'd put down a 5-figure number betting against you on that prediction.

Possibly 10 will start shipping, but how many of those will discountinue their product within 3-4 years of initial shipment, as NHT did? You forget that I own Paradigm Reference Actives myself. While not DSP, it is telling that, despite GLOWING reviews, the product line was discontinued.

There are always false starts with new technologies. Consider surround sound. Quadrophonic failed, but it worked when applied to video. It just needed to piggy back with another technology. Wireless and IP technology gives speaker companies an excuse to put DSP active technology into a speaker and consumers a reason to buy it. You could take dual Sonos units which have wireless, DSP and 2x50W amps, modify them and build them into a pair of speakers for less than $1000 added retail cost right now. It will be half that in 5 years.

I would go farther than that. If you're willing to employ an independent escrow agency, I'd put down a 5-figure number betting against you on that prediction.

I'm just giving you a chance to win back your first $100.

Besides, check out Focus Enhancement's chip that they want to put in pretty much every AV receiver/preamp for inexpensive, high resolution wireless 7.1 audio. They are having financial problems, but they could certainly sell the technology to someone like Dolby.

ok, so what are the relative advantages/disadvantages of active digital and active analog?

seems as good a place as any to ask.

ok, so what are the relative advantages/disadvantages of active digital and active analog?

If you are doing just crossovers, analog will maintain better resolution at lower volumes if the volume is happening before the crossover. But digital has so much added capability, such as more sophisticated FR, time/phase correction and more crossover flexibility.

price too?? would not analog active crossovers be considerably cheaper (even if only because they lack the extra 'goodies')

re the low vol levels, I guess you are referring to if the digital unit uses digital control?

In a passive crossover, the caps and inductors 'muck' up the phase. Even tho it is a line level, does that still happen with analog active? (I presume they rely on caps and inductors too)

price too?? would not analog active crossovers be considerably cheaper (even if only because they lack the extra 'goodies')

Not so much any more. A decent 3-way analog crossover is often $500-$5000 and some entry level DSP crossovers are now under $500. A lot of extra circuitry in a passive crossover.

re the low vol levels, I guess you are referring to if the digital unit uses digital control?

Yes, or if the signal is coming in analog with a variable analog preamp upstream. If you tune it right, it's not a big deal though.

In a passive crossover, the caps and inductors 'muck' up the phase. Even tho it is a line level, does that still happen with analog active? (I presume they rely on caps and inductors too)

Yes, just a smaller signal and less signal loss, no intermodulation with the drivers. Digital crossovers will still alter phase, but not in a way that would be noticeable as it is so gradual and at least you can easily add delay do the mid/tweeter rather than slope the cabinet.

Hey, NIN, are you saying that the *only* speaker you can think of that can match an NHT Xd's combination of qualities comes from an obscure Swedish company with no exporting? Because, if so, isn't that a pretty good argument for digital active speakers?

A decent 3-way analog crossover is often $500-$5000 and some entry level DSP crossovers are now under $500. A lot of extra circuitry in a passive crossover.

Oh, PLEASE! When you sold NHT you seemed to think the Classic 3 just a great little speaker. The entire speaker has an msrp of what, $400 each? Parts content might be in the area of $100, going by industry standards...including drivers and cabinet. How much is the crossover, John, $500?

Oh, PLEASE! When you sold NHT you seemed to think the Classic 3 just a great little speaker. The entire speaker has an msrp of what, $400 each? Parts content might be in the area of $100, going by industry standards...including drivers and cabinet. How much is the crossover, John, $500?

Relax. The Classic Three *is* a great speaker, for a passive bookshelf. Retail was $500 each, cost to build was probably $150 each, maybe a bit more knowing NHT. Do you think Behringer builds and sells their DSP crossover at cost? It is probably $75 to build, $100 max. Look at a $400 receiver with all of the unnecessary Dolby/DTS licensing fees. It costs maybe $150 to build including fees and contains all the processing power and amplification needed to run a DSP speaker if reconfigured, including remote volume and digital inputs. So, you could build basic DSP capability, in bulk, into any speaker for $500-$1000 retail price. So a DSP'ed Classic Three could be $2000/pr very easily, even with an outboard box. But Sony could build something like that for $1000 if they chose to do so. Wireless IP capability would add no more than $500 to the retail.

Do you really think that in 10 years, companies are going to be clinging to passive crossovers in expensive speakers when other companies are offering up custom OEM solutions that have wireless and DSP for only $500 per speaker retail and doubles or quadruples the price range in which the speaker can compete? Or that they're going to stand by and while getting beaten down by a company like Denon/Boston, Harman/JBL/Infinity or NAD/PSB that started implementing these as soon as it was available? Because some of those companies are already looking at introducing wireless IP receivers and speakers next year. The processor/amps in the Xd added $3K to the price because of production inefficiencies, doubling its cost, but allowed a $6K speaker to play with $20K and up speakers all day long.

It's inevitable. In fact, I dare say they might take over mass market before they take over high-end ........

While I agree with John on very little, on this issue I think he is dead on. Us die-hard over 50 audiophiles will hang onto our old ideas until we can't hang on any longer..... but ultimately we will have to let go (or just die).

I heard a prototype speaker that John Dunlavy built years and years ago (he had it at CES) with electronic/active crossovers, and while crude in many respects, it had some serious advantages in many areas over passive speakers. It will only be a matter of time when the Theils, Wilsons, Vsndersteens, etc will develop digital speakers. And when that happens (and I am sure it will), it will open the gates. Is it two years? Five? I don't know but I agree with John (it almost hurts to say that) that it is inevitable. And having heard the possibilities, I welcome the day.

It is just going to take someone with both money and commitment to pull it off (CORRECTLY!!!!) and Dave Wilson might be just the guy to do it.... Go Dave!!

It is just going to take someone with both money and commitment to pull it off (CORRECTLY!!!!) and Dave Wilson might be just the guy to do it.... Go Dave!!

That might cut into his sports car and travel budget though ;)

A decent 3-way analog crossover is often $500-$5000 and some entry level DSP crossovers are now under $500.

OK, so you meant retail. But the Classic 3, a great speaker in your view, RETAILS for $400 each. If it is a great speaker must it not have at least a decent crossover? Somehow I don't think the retail value of the crossover is $500, if the ENTIRE SPEAKER retails for $400.

It will only be a matter of time when the Theils, Wilsons, Vsndersteens, etc will develop digital speakers. And when that happens (and I am sure it will), it will open the gates. Is it two years? Five? I don't know but I agree with John (it almost hurts to say that) that it is inevitable. And having heard the possibilities, I welcome the day.

It is just going to take someone with both money and commitment to pull it off (CORRECTLY!!!!) and Dave Wilson might be just the guy to do it.... Go Dave!!

Hey, I'd like this technology to proliferate and succeed, too. I wish there were more active digital choices right now. I hope I'm wrong, but I don't think it is going to happen in a major way, even in a 10-year timeframe. All Thiel, Wilson, Vantersteen, etc have to do is look at the NHT Xd's abject commercial failure despite great reviews, and Paradigm's exit from the active business despite great reviews, and conclude that developing and marketing actives / digital actives is likely a losing business proposition, outside of the pro arena.

Hey, I'd like this technology to proliferate and succeed, too. I wish there were more active digital choices right now. I hope I'm wrong, but I don't think it is going to happen in a major way, even in a 10-year timeframe. All Thiel, Wilson, Vantersteen, etc have to do is look at the NHT Xd's abject commercial failure despite great reviews, and Paradigm's exit from the active business despite great reviews, and conclude that developing and marketing actives / digital actives is likely a losing business proposition, outside of the pro arena.

While you may be correct, I believe it is (among other things) a matter of great marketing. And who but a guy that can sell speakers that cost $150,000 to develop a great marketing approach for active speakers.

And if John is correct that this technology will fly quite well for Mid-Fi (and I also agree that he is correct) the high enders can be left behind. That is NOT where the money is.

It should be an interesting trip.

OK, so you meant retail. But the Classic 3, a great speaker in your view, RETAILS for $400 each. If it is a great speaker must it not have at least a decent crossover? Somehow I don't think the retail value of the crossover is $500, if the ENTIRE SPEAKER retails for $400.

I'm not saying you can just drop in a DSP crossover and amps at the same price. However, the increase in performance more than pays for it. The Classic Three has some of the best drivers you can get in it for DSP design and only retails for $900 pair. (sorry, it's the Era D5 that is $1000/pr now). While pulling the passive crossover won't save that much (maybe $50/pr retail), adding in an amp/DSP package would only bump them up to $2000-$2500/pr.

While you may be correct, I believe it is (among other things) a matter of great marketing. And who but a guy that can sell speakers that cost $150,000 to develop a great marketing approach for active speakers.

I don't think Wilson could build the best DSP speaker, certainly not one worth the price (I think his acoustic design leaves a lot to be desired, especially for DSP applications), but if he were to make a $200K+ flagship, it would legitimize DSP in a pretty big way, so I'm all for it. BUT, if you DEQXed a Wilson, it wouldn't sound like a Wilson, so he'd have to do it in a way that allows the boom/sizzle flavor come through. Thiel is already doing IP wireless stuff, Meridian is working towards wired/wireless IP. I think Vandersteen is increasingly a prospect for a DSP speaker (the supposed advantages of time/phase accuracy with far lower distortion, though it might also kill their gig). JMLab is a leading contender for a DSP speaker, as is B&W. If any two of these companies jump, the rest will follow.

And if John is correct that this technology will fly quite well for Mid-Fi (and I also agree that he is correct) the high enders can be left behind. That is NOT where the money is.

The question is whether it's a parallel development in the mid-fi/high-end worlds or whether mid-fi takes the lead and starts to make high-end seem irrelevant and out of touch. If hi-rez wireless 7.1 is the next big standard feature on receivers (and what else is out there?), there's going to be a huge rush to build the speakers that can take advantage of this and at really low prices. Of course, some would still have passive crossovers at the cheap end, but it won't be that much more to add another amp or two and the DSP chip. Some digital amps have DSP capability built in. You can also easily replace a 100W amp with 2 50W amps.

As an aside, if anything comes from the implosion of NHT, it will be a wireless DSP speaker. At least, that's what they've been talking about.

I don't think Wilson could build the best DSP speaker.....

There are many who would argue that Wilson does not build the best non-DSP speaker. Dave Wilson, whether you like his speakers or not, is a great marketing guy. Unlike many before, during and after him, he is still very relevant in the high-end audio business, and still around. He does not have to build the best DSP speaker to be successful.

John Dunlavy built technically great speakers but he sucked at marketing. It is ALL about marketing.

Should Wilson decide to do this, trust me that he will be very successful doing so.. with or without the best solution.

And I don't know how long it has been since you heard a great Wilson speaker, (apparently a long time) but it is not "sizzle and boom" by a long shot (and I have owned Wilsons and heard lots of them).

I agree totally, except for the boom/sizzle thing (which shows up again and again and again in measurements) :)

JMLab is a leading contender for a DSP speaker

Interesting that you should drop that name. Have you guys considered why Focal-JMLab and Dynaudio HAVE NOT taken the digital actives they have in the pro world and introduced the same technology on their consumer sides? Maybe they've concluded that such speakers are unlikely to succeed, commercially.

http://www.focalprofessional.com/en/products/SM11-home.html

http://www.dynaudioacoustics.com/Default.asp?Id=2846

I don't have access to any current measurements of the Alexandra II but have YOU actually LISTENED to them in a great room? They are NOT sizzle and boom. It is certainly OK if you don't like them but that decision would best be made after you actually listen to them in a great room.

Interesting that you should drop that name. Have you guys considered why Focal-JMLab and Dynaudio HAVE NOT taken the digital actives they have in the pro world and introduced the same technology on their consumer sides? Maybe they've concluded that such speakers are unlikely to succeed, commercially.

http://www.focalprofessional.com/en/products/SM11-home.html

http://www.dynaudioacoustics.com/Default.asp?Id=2846

Sure, but I think it's a matter of time. I spoke with Mark Glazer of Revel and he said that he could easily design a better Ultima with DSP, but they're worried about demand. It's a chicken/egg thing. Sonos was almost impossible for us to sell in 2005 despite massive efforts. By 2006, we had a reasonable trickle of customers. By 2007, it was our biggest selling product. The product didn't change, the marketing didn't change, it was customer attitudes and knowledge. Even that is the tip of the iceberg.

I don't have access to any current measurements of the Alexandra II but have YOU actually LISTENED to them in a great room? They are NOT sizzle and boom. It is certainly OK if you don't like them but that decision would best be made after you actually listen to them in a great room.

Well, true that the more affordable ones are measuring increasingly accurate (as in less boom and sizzle), but c'mon, you've seen the measurements of the Maxx2, right? +8 in the treble bass, as much as -8 in the midrange? that's like a whole new level of boom/sizzle! Add DEQX and the Maxx2 would be 1/10 that inaccurate and retain all the other things people seem to like about them. Or......maybe not ;)

John, apart from people just liking to be able to pick their amps, wouldn't you expect reliability might not be as good as with passive crossovers?

In the near term, maybe not, though if you look at Meridian, we've had incredible reliability from them. I would expect that modern amp/DSP packs could last 15-20 years with little to no problems and would allow for indefinite upgrading of the speaker if newer, better drives come out. Plus DSP speakers are less likely to fail due to high spl 'oops, I had too much to drink' events. So driver failures would likely go down as an offset.

John: One more time. Have YOU actually LISTENED to the X-2's in a great room? How about the newly updated Maxx?

John: One more time. Have YOU actually LISTENED to the X-2's in a great room? How about the newly updated Maxx?

No, I haven't really pursued it because of the measurements/design vs cost. I'm sure they don't sound bad, but I've heard lots of 'rave' 5-figure speakers that simply make me scratch my head. And, really, should a $45K speaker require an update to be less than +/-8dB? But that's a whole 'nother discussion. In my mind, these speakers are dinosaurs, even though they could get a DSP retrofit and benefit immensely.

If you'd spent the last 8 or 9 years listening to $5K-$25K DSP *and* passive speakers as I have, you'd probably understand my POV better. It's the DSP speakers that make me want to sit and listen.

No, I haven't really pursued it .....[but] these speakers are dinosaurs,

There is an expression I used in the corporate world that fits you perfectly: "If the only tool I have is a hammer, all problems look like nails". You are totally blowing off (dinosaur?) a speaker that you have not listened to because - pick one: (a) it cost too much (b) it's ugly (c) I don't like it's (X-2's) measurements (that I haven't actually seen) (d) I don't like Dave Wislon (e) all of the above or (f) I don't carry the product. (g) I'm just incredibly biased.

There is an expression I used in the corporate world that fits you perfectly: "If the only tool I have is a hammer, all problems look like nails". You are totally blowing off (dinosaur?) a speaker that you have not listened to because - pick one: (a) it cost too much (b) it's ugly (c) I don't like it's (X-2's) measurements (that I haven't actually seen) (d) I don't like Dave Wislon (e) all of the above or (f) I don't carry the product. (g) I'm just incredibly biased.

A and C (Maxx2).

What is more sophisticated and more costly to build, an X2 or an Audi RS6?

I do have a bias against D'Appolitos and 3-way passive design. 3 different sized drivers just doesn't cut it and D'Appolitos are a mess, it doesn't matter *who* does it (or even with steep DSP crossovers). NHT's D'Appolitos had issues I didn't like and did things worse than their non-D'Appolito designs, but at least they were less than $2000/pr. They were replaced with 4-ways which were *substantially* better. I'll be interested in hearing a Maxx or X2 when it measures as well as a $2500 pair of NHTs, which is to say, probably next life time :D

http://www.stereophile.com/images/archivesart/wilmaxx2fig3.jpg

Let me put it this way, if someone offered to give me a pair of X2s or a pair of Revel Studio2s, both with DEQX and professionally optimized in an anechoic chamber, I'd take the Studio2s without hesitation. Why? Engineering choices, pure and simple. Well, maybe the difference between engineering choices and marketing choices.

PS - why is it that, to an 'audiophile', "doing it right" is an expression of big money (or brand name) rather than great design and engineering?

In the end, I agree with you that it doesn't matter because Wilson has good marketing and clout, so I'd love to see him build one because that's good for everyone.

What speaker does that F/R graph represent? By the way, does your business/store have a web site?

Have measurements?

Edit - can you do better than a just beyond DIY brand sold only in Sweden?


Do better? Where there any "it must be so big brand" or "it must sell as much" to be counted? In that case the NHT would not count at all or?
It is the best speakers I have heard in the term of "correct" reproducing of the source.

was that wilson speaker a big seller, or considered one of the successful ones?? (properties says it's a maxx 2) cause I have to say that one glance at it is enough to rule it out for me as well. By ANY yardstick, how could it be described as hi fidelity?

Is it one of his less expensive 'mid' fi models?

I am really curious, the argument always comes up that FR does not tell the whole story, so what could be the possible subjective responses to that that is pleasing? That bass hump alone would be enough to be annoying within a few minutes, (for me of course, not trying to be provocative but genuinely curious).

Just using that alone as an example, could it simply be that people who like it have never been exposed to good accurate bass? (is it capable of getting good solid extension without that artificial boom even?) Often you do not know how good bass is until you can directly hear when the boom is gone. I have often smoothed peoples bass (eq only) and it can be a shock that what they are used to hearing has been highly coloured until they can suddenly hear it gone.

Until then they just didn't know (and I'm usually talking about room induced aberations, let alone a deliberately engineered natural bass boom)

Unless his crossover skills were insufficient to get a better response? (how else to explain everything above 200 hz too?)

What speaker does that F/R graph represent? By the way, does your business/store have a web site?

Maxx2. I do.

Do better? Where there any "it must be so big brand" or "it must sell as much" to be counted? In that case the NHT would not count at all or?
It is the best speakers I have heard in the term of "correct" reproducing of the source.

Well, c'mon. I could claim the same about a speaker I built in my garage, but how could anyone verify it? I mean something Stereophile or Soundstage might actually review or I might be able to hear if I drove 500 miles. Besides, when people put the term "correct" in parenthesis, it usually means "euphonic the way I like it".

John, if you were going to design an active three way with available diy drivers, cost no object, with the DEQX as the crossover, what would you build?

Ok to assume a pair of subwoofers to handle high output below 40hz or so if that's part of the concept.

Well, c'mon. I could claim the same about a speaker I built in my garage, but how could anyone verify it? I mean something Stereophile or Soundstage might actually review or I might be able to hear if I drove 500 miles. Besides, when people put the term "correct" in parenthesis, it usually means "euphonic the way I like it".


I prove it the same way you are proving that digital active crossover is the best, by saying it. So why on earth is your comment more valuable than mine?

Is it one of his less expensive 'mid' fi models?


$45,000/pr. Maybe more now.

I am really curious, the argument always comes up that FR does not tell the whole story, so what could be the possible subjective responses to that that is pleasing? That bass hump alone would be enough to be annoying within a few minutes, (for me of course, not trying to be provocative but genuinely curious).

Could be, but just as I wouldn't buy a "great" $107K speaker that is incredibly high in distortion, I wouldn't buy a "great" $45K speaker that's incredibly inaccurate. I'd rather have a speaker that measures reasonably well in every way.

Just using that alone as an example, could it simply be that people who like it have never been exposed to good accurate bass? (is it capable of getting good solid extension without that artificial boom even?) Often you do not know how good bass is until you can directly hear when the boom is gone. I have often smoothed peoples bass (eq only) and it can be a shock that what they are used to hearing has been highly coloured until they can suddenly hear it gone.

I got exposed to very accurate, very precise acoustic suspension and/or servo subs early on and it ruined me for most ported speakers and subs. There are some that don't sound ported, such as the Revel Ultimas, but they're few and far between. Most people think that's the way bass is supposed to sound.

I prove it the same way you are proving that digital active crossover is the best, by saying it. So why on earth is your comment more valuable than mine?

I've got measurements and reviews on my side, as well as probably a dozen people on AVS that own them, plus dozens of my own customers and hundreds of people who have heard them and said that they were the single best speakers they've ever heard.

... hundreds of people who have heard them and said that they were the single best speakers they've ever heard.
:eek::eek::eek:

Maybe I ought to get my hearing checked. I wouldn't put them in the top 100 of speakers I've ever heard.

Every dealer I've ever talked to has similar anecdotes.

John, if you were going to design an active three way with available diy drivers, cost no object, with the DEQX as the crossover, what would you build?

I'd probably use a single W15 as in the Tikandi and Xd, but crossed over at 300Hz or so to solve the compression issues, I'd probably use one of those new diamond tweeters from Accuton (I think), and not sure about the bass drivers, but it would probably be 3 8" metal woofers, possibly SEAS, but there are others. NHT developed some really nice magnesium 8" woofers from a Chinese manufacturer that were pretty cool for their top of the line, $20K/pr 4-way DEQX system

Ok to assume a pair of subwoofers to handle high output below 40hz or so if that's part of the concept.

Well, hmmmmmm, if that were the case, I'd do the same thing (think Revel Studio2s) and I'd build a 4' tower o'bass with 4 12" woofers per side, and add in a standard analog active crossover for the subs.

:eek::eek::eek:

Maybe I ought to get my hearing checked. I wouldn't put them in the top 100 of speakers I've ever heard.

There aren't 100 speakers in existence that are even in the same league as Xd, let alone better, so, yes, hearing check might be in order. Or, at least, a blind fold to remove bia$.

Every dealer I've ever talked to has similar anecdotes.

All two of them? All which sell really expensive speakers, really expensive cables, really expensive amps, really expensive...........? As one California Xd buyer told me, from memory "He kept trying to sell me B&W 800s, but when I told him that the Xds were clearly better, he leaned over and offered to sell me the demos because they wanted to get them out of there. And so I did".

High-end dealers don't dislike them because they're bad, they dislike them because they're that good and a deadly threat to their placebo business. That's what keeps my competitor going - mediocre, but high profit passive speakers followed by tens of $thousands of ancillary "upgrades".

Bia$? Coming from a dealer? Hmmmmmmm.....

FWIW, the most expensive speakers I've ever purchased had an MSRP of $18K. But I sure like to hear/experience as many speakers as I can, in all price ranges, if for no other reason than the fun of it. I just like experiencing music, whether I'm playing it on guitar or bass, or listening to CDs. Heck, as I'm typing this in my office I'm listening to a Sonos system right now which to date has about 1100 of my CDs in FLAC format feeding a pair of Era Design 4s (which I know you also enjoy).

Two dealers? You have tremendous powers, Carnac. Of course, you're spot on. One was at Pacific Stereo, 20 years ago, before they folded. Or maybe it was Good Guys. The other dealer I met in an alley, cash transaction ... oops, I guess I should just keep that to myself.

Of course, you also must be spot on regarding the inventory and motivation of high end dealers because, after all, you're Carnac. Only your anecdotes are to be deemed factual by the AVS community.

Man, you have no shame, no boundaries, nor a drop of humility in you.

Two dealers? You have tremendous powers, Carnac. Of course, you're spot on. One was at Pacific Stereo, 20 years ago, before they folded. Or maybe it was Good Guys. The other dealer I met in an alley, cash transaction ... oops, I guess I should just keep that to myself.

So, how many dealers can you *honestly* say you've been to that carried Xd and ditched it because it was such a bad speaker? If anything, the reviews would bring people in and you could get people into expensive gear after crushing their dreams of a cheap system. But you know that isn't the real reason. If your business is "treatment", you don't want a "cure.

Of course, you also must be spot on regarding the inventory and motivation of high end dealers because, after all, you're Carnac. Only your anecdotes are to be deemed factual by the AVS community.

Only a small relative few of you that cling desperately to beliefs and heckle anyone who has other experiences.

Man, you have no shame, no boundaries, nor a drop of humility in you.

At least I have the ability to contribute rather than harass.

cling desperately to beliefs and heckle anyone who has other experiences

Is that from the opening paragraph of your autobiography?

High-end dealers don't dislike them because they're bad, they dislike them because they're that good and a deadly threat to their placebo business. That's what keeps my competitor going - mediocre, but high profit passive speakers followed by tens of $thousands of ancillary "upgrades".

Why do you think a discontinued speaker poses a deadly threat to your competitor's business, and what speakers do you carry to counter your competitor's offerings.

Why do you think a discontinued speaker poses a deadly threat to your competitor's business, and what speakers do you carry to counter your competitor's offerings.

It isn't now, obviously, but it could have been, especially for dealers that are selling an underpriced, overachieving digital speaker next to underachieving, overpriced conventional gear. But marketing and dealer resistance prevailed (along with a weakened and repeatedly bought/sold NHT). Only a small percentage of NHT dealers ever even ordered a set because it didn't fit their normal sales paradigm. So, we picked back up Meridian. But otherwise, I'm laying low on the over $5K/pr speakers given the economy. Right now, there's not a lot of competition going on, except to see who has the most tumbleweeds gathering.

So, how many dealers can you *honestly* say you've been to that carried Xd and ditched it because it was such a bad speaker?
Irrelevant. And, even if this was relevant, which it is not, it is a straw man argument. Neither I nor anyone to my recollection (as damaged as it is due to years of, well, I better not say) certainly did not say it was a "bad speaker", let alone "such a bad speaker".
If anything, the reviews would bring people in and you could get people into expensive gear after crushing their dreams of a cheap system. But you know that isn't the real reason. If your business is "treatment", you don't want a "cure.
I'm not even sure this point is intelligible.
Only a small relative few of you that cling desperately to beliefs and heckle anyone who has other experiences.
Ah, I get it. Your "two dealer" comment to me could not possibly be deemed "heckling" now, could it.
At least I have the ability to contribute rather than harass.
So harrassment = expression of disagreement with you, namely, that Xd is not God's gift to humankind? What you see as "contribute" many (and most assuredly I) see simply as shouting louder. Syswei, you're spot on regarding the autobiography.

Like I said, not an ounce of humility.

Irrelevant. And, even if this was relevant, which it is not, it is a straw man argument. Neither I nor anyone to my recollection (as damaged as it is due to years of, well, I better not say) certainly did not say it was a "bad speaker", let alone "such a bad speaker".

"I exaggerate and can't back it up but it's irrelevant" As a lawyer might say "points to credibility".

Ah, I get it. Your "two dealer" comment to me could not possibly be deemed "heckling" now, could it.

Just asking for you to be honest. Sorry if that's difficult for you.

So harrassment = expression of disagreement with you, namely, that Xd is not God's gift to humankind? What you see as "contribute" many (and most assuredly I) see simply as shouting louder. Syswei, you're spot on regarding the autobiography.

No, harassment is only bothering to post when you can make negative comments or personal attacks. I don't do that to you. I don't expect you to agree with anything, but intellectual honesty would be a plus, otherwise you come of as, dare I say, a troll?

Like I said, not an ounce of humility.

Pot, kettle, black.

closed, locked, but not forgotten