I have heard from Pat & Ron that a few hi-end audio manufacturers who have been asked to submit their speakers were rather surprised with what they saw in their shipping products:rolleyes:.
I was talking to the chief engineer at a high-end speaker company which shall remain nameless. He told me that a particular very expensive speaker they made had a strange off-axis component which I should be aware of for room treatment. No big deal. I'll just place an absorber to kill the reflection at this particular angle. I asked him for more details, like balloon data in CLF or EASE format. All of a sudden, he could not be reached. No doubt, management had gotten wind of our talk and admonished him for admitting any imperfection whatsoever in their product! :)

Regards,
Terry

Perhaps you can post under a different name, Terry, and drop a hint. Otherwise, can you speak more about this off-axis component?

Perhaps you can post under a different name, Terry, and drop a hint. Otherwise, can you speak more about this off-axis component?
Nope, sorry. But any speaker is going to have its quirks, large or small. Pro audio manufacturers understand this, and provide the necessary data so that other pros can utilize their products most effectively. But many audiophile equipment manufacturers seem to exist on the illusion of perfection, if not downright transcendence!

Nope, sorry. But any speaker is going to have its quirks, large or small. Pro audio manufacturers understand this, and provide the necessary data so that other pros can utilize their products most effectively.

How often does this really happen? Do many "pro" speaker makers provide the data needed to understand their speakers, and do many "pro" speaker users know how to interpret this data? What is this data? Unless I misread is it basically frequency response as a function of angle. Do you think that is all that is needed? Seems like CLF is just trying to get off the ground. How useful do you think this data might be in a "home" setting? I'm guessing you'd like to have all home listeners hire you (or somebody similar) to pick their speakers for them, and design the room around the speakers. How well do these CLF data translate into a typical "small" home listening room?

If you were going to design your ideal home listening room, what would you do first - design the room, or pick the speakers? How do you account for user preference - or is that really needed at all?

How often does this really happen? Do many "pro" speaker makers provide the data needed to understand their speakers, and do many "pro" speaker users know how to interpret this data? What is this data? Unless I misread is it basically frequency response as a function of angle. Do you think that is all that is needed? Seems like CLF is just trying to get off the ground. How useful do you think this data might be in a "home" setting? I'm guessing you'd like to have all home listeners hire you (or somebody similar) to pick their speakers for them, and design the room around the speakers. How well do these CLF data translate into a typical "small" home listening room?

If you were going to design your ideal home listening room, what would you do first - design the room, or pick the speakers? How do you account for user preference - or is that really needed at all?

My simplistic opinion is that the the Pro audio world is more about true performance because we are talking about serious output and SQ needs here.

There is a lot less subjectivity surround the pro audio world too. Just look at the amps and the speaker choices and you realize that its all about performance and zero about looks.

The people buying the pro stuff are usually in some sort of audio business themselves so they have some knowledge about what is truely going on out there.

Not surprising to me though is the fact that DIYers realize the performance gains from choosing pro amps/pro drivers, etc. Its a different world for many of us out there vs all those people spending time on audio boutiques.

Im definitely not the expert here but if I was to build a custom room for any of my friends. I would make sure the room was built properly with all the correct treatments, I would then find the speakers that measured very well and fit their listening distance/SPL requirements. I would install the system in room and have EQing equipment available to tweak speakers if they person refuses to learn what properly calibrated systems sound like....I believe in the world of custom setups....Warm, Detailed, Bright and so on is not professional at all.

Somebody apparently said:

"People who listen primarily to the music could in general care less what the recording sounds like."

I don't agree with this. I listen to the music. I care about how it sounds. I search out better recordings of things I like, and, I try to make them sound as good as possible.

When I was 10 I was happy enough just to have the music, at 12 I started tweaking things in an attempt to make it sound better. That was many many years ago, and I'm still working on it. Perhaps I'm not a typical listener, but I have not met anybody who
likes music who does not like it recorded and played back as well as possible. Yes I listen to some poorly recorded music, on crummy systems, and I can enjoy that - but I could enjoy it even more if it was well recorded and played back on at least a decent system.

My simplistic opinion is that the the Pro audio world is more about true performance because we are talking about serious output and SQ needs here.

I've heard some "pro" audio that was very well done. I've heard others that were crap. It is a different world. They have the advantage of a larger room, but they also have the disadvantage of trying to fill that room with sound. Outdoors might be both easier and harder.

There is a lot less subjectivity surround the pro audio world too. Just look at the amps and the speaker choices and you realize that its all about performance and zero about looks.

No doubt not having to worry (much) about aesthetics reduces cost.

The people buying the pro stuff are usually in some sort of audio business themselves so they have some knowledge about what is truely going on out there.
That can be hit and miss in my experience


Not surprising to me though is the fact that DIYers realize the performance gains from choosing pro amps/pro drivers, etc. Its a different world for many of us out there vs all those people spending time on audio boutiques.

I've seen more than one DIYer been fooled into thinking what they are
doing is the best. Sticking "pro" drivers into a homemade box does not
guarantee success. Just like going to a "boutique" and listening does
not always get the best result. The DIY has spent less money,
but that does not mean what they built is better than what they
could buy.

Im definitely not the expert here but if I was to build a custom room for any of my friends. I would make sure the room was built properly with all the correct treatments, I would then find the speakers that measured very well and fit their listening distance/SPL requirements. I would install the system in room and have EQing equipment available to tweak speakers if they person refuses to learn what properly calibrated systems sound like....I believe in the world of custom setups....Warm, Detailed, Bright and so on is not professional at all.

I'm not an expert either. But I do want to keep learning and improving my music listening experience. I'm not convinced that being professional about this will increase my pleasure.

Somebody apparently said:

"People who listen primarily to the music could in general care less what the recording sounds like."

I don't agree with this. I listen to the music. ...
Well, perhaps you don't listen primarily to the music, or even if you do, since it's only in general, perhaps you're an exception. You see how useless it is to try to discuss a seemingly absurd proposition that has sufficient weasel words as to prevent it from meaning anything specific?

If I had time and money it would be fun to hire three professionals to come in and provide recommendations. I'd likely get three different recommendations (maybe more
if they are like typical experts - guilty of that myself). So then I'd use the time to try and understand what each one recommended and why. But I don't have the time or money for that, and, likely I have more time and money than many.

Well, perhaps you don't listen primarily to the music, or even if you do, since it's only in general, perhaps you're an exception. You see how useless it is to try to discuss a seemingly absurd proposition that has sufficient weasel words as to prevent it from meaning anything specific?

I have no interest in discussing semantics. You are right though - if that was the interest it would be useless.

The sound that makes guys buy $12,000.00 amps:D

KG

I presume by "loss of transmission," you do not mean "complete loss of transmission." Of course it can't scare you if you don't see/hear it.

gotta stick to my guns and say that there still is a probability of transmission however small.


But if that's not what you mean, then you are assuming your conclusion. Given that the D/A conversion happens at all, why should we think it would be scarier, or more likely to be scary, observed on a high-end system rather than through tinny computer speakers? I don't even think making it louder would have the impact you ascribe to it.


Really? As a kid I used to jump out from around the corner to scare my friends and family. There's a reason why I would yell really loud the moment I jumped out. Instinctively when you're 16 and driving around and a great tune comes on, you turn up the volume.



I don't buy the notion that highly accurate reproduction is necessary to appreciate an artist's intent. I can "get" Beethoven, and even someone's interpretation of Beethoven, on a boombox.

This is where I presume there is a relative notion to information. The units of "accurate" reproduction has a duality with phase/magnitude/frequency. Phase/Magnitude/Frequency are units relative from the the voltage send/recieve relative to me. Accurate reproduction as I define it is from the musician to me. A 100% transmission can only occur between the musician and the musican or me to me. That's because I am in the same state as me and the musician is in the same state as that musician.

If I were to change (mental = physiological) then the transmission probability goes down. So say I write a letter to myself and unbury it in 10 years. Much of the content, including the subconcious content I wrote to myself is lost. All that is transmitted is the literal content and the details to which I remember motivated me to write the letter (similar state).

My explaination of how a 13mb mp3 can be the "same" as a 55mb pcm:
The units are not in units me to me but units of the digital sender/reciever relative to me. Just as I might examine the waveform of a piece of music. Those units (x and y axis) are not in units of me to me but units of microphone/speaker relative to me.
As a consequence there is some similarity of the microphone/speaker to me in that we share a similar state. At the most basic level our xyz/time coordinates in the universe are pretty close.
The waveform and what I hear have a duality. They are one in the same but depending on the reciever they are recieved differently and retransmit differently. I might have a signal that is frequency shifted by 15kHz. I can look at a plot of the spectral power and it retains 99% of the "meaning" as the unshifted plot. However if I listen to the signal, it has no "meaning". When I alter the frequency, the probability transmission from the a/d, d/a to me is high but the musician transmission to me is low.

Accurate reproduction as I define it is from the musician to me
Then you are not talking about audio reproduction at all. You're talking about some metaphysical "connection" in which the use of the word "accuracy" makes no sense. Further discussion would be pointless.

But to me, being an audiophile and being a music lover are two different things.

;) Because the speaker is transmitting to you too.


I very much prefer a digital display to an analog one (ie CRT or film) In fact I like a touch of screendoor. From a signals perspective the step function generates an abomination of noise. The step function is generated by slicing the display along an axis and ploting the magnitude of blue. It is a consequence of pixel interpretation of ideal sampling. However as a visual reciever the "sharpness" of the step relaxes my eye and doesn't make me dizzy. There is an aesthetic quality of the sharpness which comes from the display/camera and pleases me.

Nope, sorry. But any speaker is going to have its quirks, large or small. Pro audio manufacturers understand this, and provide the necessary data so that other pros can utilize their products most effectively. But many audiophile equipment manufacturers seem to exist on the illusion of perfection, if not downright transcendence!OK then can you provide some information regarding some pro speaker with respect to the information that's provided and how other professionals can use that to their advantage? I'd rather hear about the other, but...

OK then can you provide some information regarding some pro speaker with respect to the information that's provided and how other professionals can use that to their advantage? I'd rather hear about the other, but...
Go to the CLF link that Mark provided earlier. Download the free CLF viewer, and any of the many CLF speakers files linked to from this site.

You can then among other things display the 3D "balloon plots" of a speaker at any selected frequency. This gives quite a stunning snapshot of the directivity which visually conveys more information than a 2D polar plot.

The most common pro usage for this data is in computational modelling of room acoustics. You plug the speakers you intend to use into an acoustic room modelling program (Odeon, EASE, etc.) which contains the 3D room model. You can then run a detailed simulation to predict the finished room's acoustical measurements and quality. The 3D CLF speaker data improves the accuracy of the simulation.

I've heard some "pro" audio that was very well done. I've heard others that were crap. It is a different world. They have the advantage of a larger room, but they also have the disadvantage of trying to fill that room with sound. Outdoors might be both easier and harder.



No doubt not having to worry (much) about aesthetics reduces cost.


That can be hit and miss in my experience




I've seen more than one DIYer been fooled into thinking what they are
doing is the best. Sticking "pro" drivers into a homemade box does not
guarantee success. Just like going to a "boutique" and listening does
not always get the best result. The DIY has spent less money,
but that does not mean what they built is better than what they
could buy.



I'm not an expert either. But I do want to keep learning and improving my music listening experience. I'm not convinced that being professional about this will increase my pleasure.


All valid points that differ a little then mine, no need to argue each of them individually because we are both being subjective about it all. One thing though is that I do believe that most DIYers get it right and the ones that don't are the ones that do not building things properly. If you have DIYed anything you will realize there can be great gains in performance/$$$, I not only DIY my speakers but my HT room, my house automation, my house itself and so on.

With that DIYers in the audio world tend to go beyond the simplistic idea of searching for a specific sound (bright, warm). They tend to build something that has superior specs vs something in the same $$$ range comercially.

Perhaps you can post under a different name, Terry, and drop a hint. Otherwise, can you speak more about this off-axis component?

Quite a few companies have this issue; no need to name one offender out of many.

Concisely, most companies dealing with dipolar/bipolar front stages are problematic, but they can be dealt with.

If I were to change (mental = physiological) then the transmission probability goes down. So say I write a letter to myself and unbury it in 10 years. Much of the content, including the subconcious content I wrote to myself is lost. All that is transmitted is the literal content and the details to which I remember motivated me to write the letter (similar state).

My explaination of how a 13mb mp3 can be the "same" as a 55mb pcm:
The units are not in units me to me but units of the digital sender/reciever relative to me. Just as I might examine the waveform of a piece of music. Those units (x and y axis) are not in units of me to me but units of microphone/speaker relative to me.
As a consequence there is some similarity of the microphone/speaker to me in that we share a similar state. At the most basic level our xyz/time coordinates in the universe are pretty close.
The waveform and what I hear have a duality. They are one in the same but depending on the reciever they are recieved differently and retransmit differently. I might have a signal that is frequency shifted by 15kHz. I can look at a plot of the spectral power and it retains 99% of the "meaning" as the unshifted plot. However if I listen to the signal, it has no "meaning". When I alter the frequency, the probability transmission from the a/d, d/a to me is high but the musician transmission to me is low.

So this is how engineers express emotion!

Quite a few companies have this issue; no need to name one offender out of many.


I have worked in the supply chain/warehouse management software side of the distribution industry for almost 20 years now and I have been in 100s of warehouses looking at their order fullfilment systems,etc. We get into talking a little about the products and there are lots of times where I just say "They manufacture for those companies?" I have even been in some Audio manufacturing/distribution facilities over the years. Its amazing what the average consumer does not know. "Private Label" is a HUGE business out there.

I have worked in the supply chain/warehouse management software side of the distribution industry for almost 20 years now and I have been in 100s of warehouses looking at their order fullfilment systems,etc. We get into talking a little about the products and there are lots of times where I just say "They manufacture for those companies?" I have even been in some Audio manufacturing/distribution facilities over the years. Its amazing what the average consumer does not know. "Private Label" is a HUGE business out there.

Businesses have long realized that consumers tend to obsess and attribute too much weight to ultimately meaningless trivia surrounding the things they buy.

Businesses have long realized that consumers tend to obsess and attribute too much weight to ultimately meaningless trivia surrounding the things they buy.


That's what the high-end audio business runs on.

That's what the high-end audio business runs on.

Conversely, intelligent businesses choose not to be completely transparent on things they know are truly irrelevant, because they know that the majority will typically misinterpret the issue anyway.

It's silly to have to waste resources to defend against meaningless issues.

Conversely, intelligent businesses choose not to be completely transparent on things they know are truly irrelevant, because they know that the majority will typically misinterpret the issue anyway.

It's silly to have to waste resources to defend against meaningless issues.

Given much of my experience with the high-end audio business one wonders if they can be considered intelligent businesses... :eek:

While there are some very good high-end companies out there I have seen far too many that fleece unsuspecting customers that are members of the more money than brains club. I do not consider this to be a good way to go about doing business although it might fit some people's definition of 'intelligent business'... :rolleyes:

Conversely, intelligent businesses choose not to be completely transparent on things they know are truly irrelevant, because they know that the majority will typically misinterpret the issue anyway.

It's silly to have to waste resources to defend against meaningless issues.

So you are really saying they just prey on the ignorance of 99% of the population ;)

and prey, too. ;)

and prey, too. ;)

lol, oops! :D

That's what the high-end audio business runs on.

One need only visit a high end audio exhibition to realize this.

There is a legitimate segment of the high end audio business that involves selling truely relevant high performance at a correspondingly high price.

Unfortunately for the suppliers, the price of just about everything electronic, when built to the highest reasonble standards, is now commoditized.

This leaves loudspeakers, room acoustics, and extreme conveniences such as whole-house audio, as ust about the only productive markets for a high end supplier.

What is the opinion here on "polar maps"

I was reading through Geddes Waveguide thread over on diyaudio.com and a member was using "Polar maps"

http://www.diyaudio.com/forums/showthread.php?s=&postid=1791851#post1791851

Dr. Geddes posted "... There are very nice looking with great detail. I hope that it is clear how polar maps "tell all". It is the complete story and nothing less is sufficient to make any "sound" (pun intended) judgements." and ".....The advantage of a polar map is how much it can tell you at a single glance...."

I have never heard of them, time to do some research.

I love that thread the more I read it .....

Dr Geddes Quote:

"The point that I think that you are missing is how really insignificant good sound quality actually is in the marketplace. Its not about sound quality, its about image and what people "think" will sound good, and oh yes, does the cabinet "look good". Real sound quality does not driver the industry, in fact it hardly even rates at all."

I love that thread the more I read it .....

Dr Geddes Quote:

"The point that I think that you are missing is how really insignificant good sound quality actually is in the marketplace. Its not about sound quality, its about image and what people "think" will sound good, and oh yes, does the cabinet "look good". Real sound quality does not driver the industry, in fact it hardly even rates at all."

want an example? It's fun to see reviews of 'high end ' loudspeakers in contrast to the measurements.

reviews

http://www.positive-feedback.com/Issue11/zudruid.htm
http://www.soundstage.com/revequip/zucable_druid.htm

measurements (not truly polar but incorporating off-axis response):

http://www.soundstagemagazine.com/measurements/zucable_druid/

want an example? It's fun to see reviews of 'high end ' loudspeakers in contrast to the measurements.

reviews

http://www.positive-feedback.com/Issue11/zudruid.htm
http://www.soundstage.com/revequip/zucable_druid.htm

measurements (not truly polar but incorporating off-axis response):

http://www.soundstagemagazine.com/measurements/zucable_druid/

lol, I have seen the Zu measurements before :D

What is the opinion here on "polar maps"

Post #266 ?

Go to the CLF link that Mark provided earlier. Download the free CLF viewer, and any of the many CLF speakers files linked to from this site.

You can then among other things display the 3D "balloon plots" of a speaker at any selected frequency. This gives quite a stunning snapshot of the directivity which visually conveys more information than a 2D polar plot.

The most common pro usage for this data is in computational modelling of room acoustics. You plug the speakers you intend to use into an acoustic room modelling program (Odeon, EASE, etc.) which contains the 3D room model. You can then run a detailed simulation to predict the finished room's acoustical measurements and quality. The 3D CLF speaker data improves the accuracy of the simulation.

"Post #266 ?"

Thanks!

Given much of my experience with the high-end audio business one wonders if they can be considered intelligent businesses... :eek:

While there are some very good high-end companies out there I have seen far too many that fleece unsuspecting customers that are members of the more money than brains club. I do not consider this to be a good way to go about doing business although it might fit some people's definition of 'intelligent business'... :rolleyes:

Not to use too broad of a brush, but I applaud any company that takes full advantage (legally) of it's intended target market. If people want to spend money on looks, sound, name perception, or voodoo, fine. This is a free market, and since performance issues tend to be subjective form person to person, it's hard to disprove a lack of benefit for a given product.

another great link I have found and read through....

http://www.nutshellhifi.com/library/speaker-design1.html

Lots points in that link that are repeated in this thread.

Two specific points in that link are very interesting....

"In speakers that measure "textbook-perfect," this type of "hidden" resonance is the dominant source of coloration. This is also the reason that 1/3 octave pink-noise measurement techniques have fallen out of favor, being replaced by much more revealing techniques such as TDS, FFT, MLS, and others."

"People actually hear the world in quite different ways, and different people assign importance to different qualities of sound. Some audiophiles value tone above all else, treasuring the sound of their favorite instruments or voices; some like a sense of immediacy, directness, and emotional impact; some like the sensation of an immense 3D space; and others like a see-through transparency, a palpable "you are there" quality."

another great link I have found and read through....

http://www.nutshellhifi.com/library/speaker-design1.html

Lots points in that link that are repeated in this thread.

Two specific points in that link are very interesting....

"In speakers that measure "textbook-perfect," this type of "hidden" resonance is the dominant source of coloration. This is also the reason that 1/3 octave pink-noise measurement techniques have fallen out of favor, being replaced by much more revealing techniques such as TDS, FFT, MLS, and others."

"People actually hear the world in quite different ways, and different people assign importance to different qualities of sound. Some audiophiles value tone above all else, treasuring the sound of their favorite instruments or voices; some like a sense of immediacy, directness, and emotional impact; some like the sensation of an immense 3D space; and others like a see-through transparency, a palpable "you are there" quality."

Two very good points. I concur. :)

Then you are not talking about audio reproduction at all. You're talking about some metaphysical "connection" in which the use of the word "accuracy" makes no sense. Further discussion would be pointless.

my attempt is actually to resolve "metaphysical connections" into something physical. When it is physical, it is modeled, and inherent with models is the ability to communicate that information to another person.

Information and communication (the transmission of information)are relative. Relative to the observer or as I call it the reciever. This definition is for all communication.
You take an AM transmission to 2 recievers. One reciever has a clear line of sign from the transmitting antenna..it gets a clear signal; proper transmission. The other reciever has to go through trees and water; it has a poor transmission. In this example the measured distance..the xyz coordinate of one reciever to the other is the differentiating factor which affects the communication. the corresponding measured distortions are objective only because you and I can commonly interpret the data...ie we have common knowledge and common understanding. If I were to parallel transmit that distortion information(measured data) to a nontechnical person it has no meaning and suddenly it is subjective. Here I have taken the same measured data and shown it can be subjective.

Example 2. Polar plots. Polar plots are extremely subjective...why?
I have faith that jj and mark and terry can openly discuss the interpretation of a common measured polar plot because they have:
common knowledge
common technical background
common experience (with how particularly shaped polar plots "sound").

where as I am lacking in all of those categories, relative to that company and relative to the information in the polar plot. They can describe it all they want but the units they would be talking in would be all fluffy and flowery compared to the real 1st hand experience of listening to a particular polar plot. A mathematical description of the experience is still fluffy and flowery. A technical description of the experience is still fluffy and flowery. The math behind it all is only accepted as "objective" because the units behind math are considered "objective" because you and I understand math on the same level..we have the same language..we have the same common experience.

Example 3. We have a scale and a weight. The scale is uncalibrated. The weight measured on the scale is 2 lbs. I say it is 2 lbs and you say it is not 2 lbs but probalby 2 lbs 1ounce. Relative to both of us the information transmitted from the scale is subjective. It is subjective because we do not agree on the validity of the scale. So somebody will say that there is a true value of the weight. That true value is only really true if everybody agrees upon it. Otherwise if you believed in its "truth" that value would only be valid to a higher being such as God or your highschool math teacher or the worlds smartest physicist. Now the "truth" is entirely based on your "faith".

The nature of information is that it is multilayered. It is a direct consequence of being relative to the observer. If all observers were the same then there would be no multilayeredness.
We are observing the same illustration of a blue ball. we both agree it is blue. we both agree it is a ball. Those are our common units.
I see a blue ball I played with in my childhood and lost to the neighbours dog. You see the beauty in the circle and the mathematical harmonys it represents.
The same illustration transmits the same information to us and the information we recieve is different from our uncommon experience.

Now if this seems silly it resolves into some consequences.
1. What we measure is useless unless it is corelated with common units. Units that can be agreed upon by nearly everyone.
2. Measuring to no end of precision without regard with to the common units is fool hardy. That's like designing for 8 decimal places when all you need is 2 significant digits.
3. Ultimate evaluation of any system must be performed at the highest end user level. Anything else will simply result in an "interpretation" of the real thing.

So how would I perform tests? I have a musician practice and I record the sound. After every few seconds the signal is transmited through the reproduction chain...compression, amplification, speakers, back to the musician. I ask him only one question.."is that what you played?" If he answers yes that means everything he wished to communicate, the tempo, the frequencies, the energy, the emotion was not lost. It ensures that the probability of the information he "wished" to transmit to me remains high.

I take an orchestra and record and mix as if I were to master an MP3. I would ask the conductor "is that what you performed". If I ask the orchestra then the relative communication to me is completely different.

The methodology of the line of questioning would require psychoanalysis expertise and how to process the data would require fuzzy logic expertise. Both are way beyond my capability.

So how would I perform tests? I have a musician practice and I record the sound. After every few seconds the signal is transmited through the reproduction chain...compression, amplification, speakers, back to the musician. I ask him only one question.."is that what you played?" If he answers yes that means everything he wished to communicate, the tempo, the frequencies, the energy, the emotion was not lost. It ensures that the probability of the information he "wished" to transmit to me remains high.

Having played in an orchestra or two, a couple of bands and having many musician friends I have found over the years that many musicans are, with a few rare exception, indifferent to the reproduction chain. Many of them will happily listen to a boom box and report that it sounds fine to them. It's all about performance and reproductive accuracy means almost nothing.

That's my general impression too, scientest. They don't need an audiophile system in order to enjoy an outstanding performance or critique the passage.

They can describe it all they want but the units they would be talking in would be all fluffy and flowery compared to the real 1st hand experience of listening to a particular polar plot.

Just as a note, that's insufficient, it's "a particular polar pattern in a particular acoustic situation".

In an anechoic chamber, a speaker that is flat in direct sound but has awful power characteristics can sound pretty good on axis.

Now put it in a live room.

***twitch***

Having played in an orchestra or two, a couple of bands and having many musician friends I have found over the years that many musicans are, with a few rare exception, indifferent to the reproduction chain. Many of them will happily listen to a boom box and report that it sounds fine to them. It's all about performance and reproductive accuracy means almost nothing.

Yep.

The elements of the performance that they are listening to are well, far above threshold of audibility, and they can hear what they need to hear, modulo ideas about particular instruments, without a good system.

Things like pace, rhythm, timing are characteristics that are well above threshold and can conveyed with 100-7kHz bandwidth and not the cleanest of signals.

The worst speaker in the world does not cause the violin player to sound like he or she has bad intonation, just maybe a bad violin, for instance.

I have found over the years that many musicans are, with a few rare exception, indifferent to the reproduction chain. Many of them will happily listen to a boom box and report that it sounds fine to them. It's all about performance and reproductive accuracy means almost nothing.

I think there are two main reasons for this. First no reproduction system can perfectly reproduce what is heard - in part because what a musician hears is not the same as what the audience hears. Since no reproduction system is perfect might as well not spend lots of money on one - especially since they have the experience to be able to fill in the missing pieces.

'Specially if you're a deaf mofo like Neil Young or Pete Townshend :D

Not to use too broad of a brush, but I applaud any company that takes full advantage (legally) of it's intended target market.


There's the slight matter of truth in advertising.

The fact that loudspeaker technology is still rather underdeveloped makes it tough to prosecute a speaker manufacturer on the grounds of false advertising.

If we can't prosecute cable manufacturers on those grounds, we're light years from going after people who sell to the home market for speakers.


If people want to spend money on looks, sound, name perception, or voodoo, fine.


The obvious problem is that our undereducated audiophile market doesn't know vodoo when they see it. They think that they are buying science, when it is really just vodoo in the box.


This is a free market, and since performance issues tend to be subjective form person to person, it's hard to disprove a
lack of benefit for a given product.

Hiding behind subjectivity used to be the essence of the market for medications. By changing that, economic benefits started to flow far more strongly to producers who sold products that actually worked as claimed. In the end, that fostered the past 8 or more decades of very beneficial progress in that field.

If you don't take audio seriously, it can easily become something that nobody should take seriously.

There's the slight matter of truth in advertising.

The fact that loudspeaker technology is still rather underdeveloped makes it tough to prosecute a speaker manufacturer on the grounds of false advertising.

I've never seen a speaker manufacturer tell the audience what they're going to hear and how they're going to hear it, and present that as a guarantee. It's not only borderline impossible, but I think frankly that would hurt the marketing process, since it's my belief that most listeners want to glean their own results from their own listening sessions.

If we can't prosecute cable manufacturers on those grounds, we're light years from going after people who sell to the home market for speakers.

It's too much of a moving target and not important really.

Hiding behind subjectivity used to be the essence of the market for medications. By changing that, economic benefits started to flow far more strongly to producers who sold products that actually worked as claimed. In the end, that fostered the past 8 or more decades of very beneficial progress in that field.

I understand. Obviously medical and medicinal issues are far more important than how a speaker sounds, but I see your point.

We can do all sorts of in room or outside measurements to accurately define a speaker. Correct?

Then why do people still ignore all those measurements and use "How does it sound to you" Mantra.

Does accurate speaker equate to best measured speaker? (Flat FR plot, etc)

If the goal is accuracy for some people then why don't they use the measurements instead of the flawed "How does it sound to you" appoarch?

How it sounds to them has little to do with accuracy most times. I have to believe people just think there is a missing measurement out there and therefore they have to listen.

Obviously, Im assuming accurate measurements....yes manufacturers can lie!! Lets assume a speaker has the measurements you want. Why not buy it based on those?

Everything that CAN be heard CAN be measured. That doesn't mean that current measuring devices actually DO measure it. There are lots of reasons that is true. For example, most people don't need music reproduction beyond a certain level, so there is no point in measuring beyond a certain level. Developing the technology to measure everything is technologically within our means I think, but there just isn't the financial motivation like there would be for, say, nuclear weapons technology, or cancer research, or ......

Therefore, people have to rely on their ears rather than insufficient measurements. This of course opens a Pandora's Box of problems with psychology, biases, corruption due to profit motives and conflicts of interest, etc.

Not to mention the fact that different people have different ears with different amounts of wax in them and different degrees of high frequency hearing loss, etc. (You will probably not find 2 people with exactly 20 Hz to 20,000 Hz audible range.)

There probably isn't a perfect speaker for several reasons. The most obvious one is that room acoustics plays a big role in how the sound is reproduced, and the manufacturer can never predict that aspect of it. No 2 rooms are going to be exactly alike, so it's impossible to design to work perfectly in all cases.

Also different speakers have different properties that lead to different strengths and weaknesses. So far, no single technology can do all things optimally. Maybe this is like the search for the unified theory of physics :-) Maybe someday they will invent the perfect transducer.

Having played in an orchestra or two, a couple of bands and having many musician friends I have found over the years that many musicans are, with a few rare exception, indifferent to the reproduction chain. Many of them will happily listen to a boom box and report that it sounds fine to them. It's all about performance and reproductive accuracy means almost nothing.

That's true, but it really doesn't lead to any conclusions for audiophiles. The musicians there are certainly not believing they are hearing a live orchestra when listening. And that is basically what most audiophiles are trying to recreate - a live music "event" in their own home, where they get to choose the concert selections they listen to, and when. That is quite an awesome thing, when you think about it. It certainly explains why so many audiophiles go to extreme or even insane or illogical levels to achieve it.

I think there are two main reasons for this. First no reproduction system can perfectly reproduce what is heard - in part because what a musician hears is not the same as what the audience hears.

That is quite true. What a violinist hears when he plays is quite different from what the audience hears. That is why goofy recordings with microphones placed in silly places (such as INSIDE the piano) do not sound "good". That is simply not what instruments sound like, as they were intended to be heard.

That's my general impression too, scientest. They don't need an audiophile system in order to enjoy an outstanding performance or critique the passage.

ISTR an anecdote about a famous conductor -- Eugene Ormandy I think -- whose home system was found to be rather badly out of EQ balance when it was checked by someone more technically inclined than him.

Few of the musicians I know are into audio per se -- and to the extent they are, it's usually focused on their home recording studios or getting the right sound from their instruments, not their 'stereos'.

'Specially if you're a deaf mofo like Neil Young or Pete Townshend :D

LMAO! Unbelievably funny Chu............as usual. Outstanding. :D

If you don't take audio seriously, it can easily become something that nobody should take seriously.

Very, very well said, Arny.

Thank god Ms. Spears takes it seriously!

Thank god Ms. Spears takes it seriously!

Stop it, you're killing me. :D

Not to use too broad of a brush, but I applaud any company that takes full advantage (legally) of it's intended target market.

Jibberjabber, I actually agree but with a disclaimer....Great marketing departments know how to twist it just enough to not be called on it. Look at Monster, nothing they do is illegal but its down right insulting to our intelligence, good thing for them is the fact that the majority of people are ignorant about audio science (btw, that is not a bad thing either!!)

Jibberjabber, I actually agree but with a disclaimer....Great marketing departments know how to twist it just enough to not be called on it. Look at Monster, nothing they do is illegal but its down right insulting to our intelligence, good thing for them is the fact that the majority of people are ignorant about audio science (btw, that is not a bad thing either!!)

Hence the phrase "vote with your wallet."

Hence the phrase "vote with your wallet."

Sure Caveat emptor is my motto too actually! But we both know that ignorance doesnt stand a chance, you do not care and I do care about that. I want the consumers to be educated!

btw, We are getting off topic! I really want to keep discussion on measurements :D

Sure Caveat emptor is my motto too actually! But we both know that ignorance doesnt stand a chance, you do not care and I do care about that. I want the consumers to be educated!

As long as it's education devoid of bias (especially where Monster's involved). On this forum that's tricky, and for those that aren't used to the AVS MO, it might be hard to extricate the two.

btw, We are getting off topic! I really want to keep discussion on measurements :D

Agreed.

Not to use too broad of a brush, but I applaud any company that takes full advantage (legally) of it's intended target market. If people want to spend money on looks, sound, name perception, or voodoo, fine. This is a free market, and since performance issues tend to be subjective form person to person, it's hard to disprove a lack of benefit for a given product.


Try as I might I cannot find an argument against this... :p A part of me strongly supports the idea of making it very costly to be a fool. Were more of life like that we may have to suffer fewer fools. :cool:

Try as I might I cannot find an argument against this... :p A part of me strongly supports the idea of making it very costly to be a fool. Were more of life like that we may have to suffer fewer fools. :cool:

economic Darwinism

There will never be a shortage of fools according to scientific principles - nature abhors a vacuum therebye ensuring a steady supply of fools.

There will never be a shortage of fools according to scientific principles - nature abhors a vacuum therebye ensuring a steady supply of fools.
Do quantum vacuum fluctuations create fool-antifool pairs? :confused:

Do quantum vacuum fluctuations create fool-antifool pairs? :confused:

Yes. It's the basis of our modern political system.

Unlike matter/antimatter, unfortunately they don't annililate each other. Thus... the thread still exists. :)

First of all, I'd like to say that it is extremely difficult and often misleading to make comparisons between different speakers without the use of speaker mover to control positional effects. The positional effects can easily swamp out any true audible differences between the speakers, particularly if the measured differences among them are very small. I used to find that positional effects alone could change the preference rating of a loudspeaker by 20%. That is why Harman spent considerable money on a multichannel and in-wall speaker mover -- so the positional biases are removed from the test.

Secondly, you cannot correlate what you hear to what you measure unless you have comprehensive on and off-axis data like the kind we advocate. You could be hearing brightness in a loudspeaker that has a dip at 2-4kHz on-axis because of its off-axis response. The upper-treble brightness you are hearing could also be due to the 2-4 kHz dip since the dip could produce a release in upward masking - emphasizing the frequency range above the dip. In our listener training exercises, listeners commonly mistake dips as peaks located higher in frequency.

Comprehensive anechoic loudspeaker measurements combined with the right set of in-room measurements can usually explain what you are hearing.

Cheers
Sean

Yep.

The elements of the performance that they are listening to are well, far above threshold of audibility, and they can hear what they need to hear, modulo ideas about particular instruments, without a good system.

Things like pace, rhythm, timing are characteristics that are well above threshold and can conveyed with 100-7kHz bandwidth and not the cleanest of signals.

The worst speaker in the world does not cause the violin player to sound like he or she has bad intonation, just maybe a bad violin, for instance.

Another way of looking at my proposition is that the musician is listening to himself through the reproduction mechanism. Let us assume a musician of the highest musicianship and highest integrity (a.k.a. he's a snob). He records a cut and while his performance is still fresh in his head he listens to the recording of himself which has been processed through the reproduction chain all the way through the speakers to his ears. I have intentionally frequency shifted up two notes worth. When I ask" is this what you played" he will say no. the question "is this the same as what you played?" is pretty loaded. relative to me when he listens to the playback he is listening for elements beyond my capacity. If it is his intention to communicate those elements and they are somehow "lost" and he is of the highest integrity he will say no. If he doesn't have the greatest in confidence in his memory he will want to re-record the passage on the assumption the loss of transmission was from his head to his trumpet.
when I was in highschool I went to a jazz festival and the headliner was Bill Watrous. there was a buzzing in the speakers and he kept glaring at the sound technicians to fix it. The reasons why he was angry about it only be speculated. Why would he care about the fidelity of the amplification?

My question was deliberately open to interpretation because I didn't want to bias what information content the listener was trying to detect. It is Yes or No answered because a binary response relative to me is in very similiar units. The question is simple enough so that all potential consumers can undergo the same testing procedure and understand the question as the musician. So when a consumer undergoes the evaluation and answers Yes and the musician answers yes, the units of the final transmission are the same. anything lost in the consumer is not the fault of the reproduction chain but lost from the consumer. However, the transmission from musician to consumer relative to me is 100%.
Where the psychoanalyst comes into play is that the test procedure has to have very carefully devised questions. Answering the questions the musican will be thinking of self to self, self to consumer to self, self to technician to self..etc. The consumer too has to understand the questions to result in the same units as the musician otherwise the test is inherently flawed.
(An interesting consequence of this is that relative to me I cannot create a 100% transmission mechanism from an english musician to a japanese consumer, but relative to an english/japanese translator the transmission mechanism can be 100%)

Where the Neural network scientist comes into play is that their expertise is in creating weighted values based on binary input. They also can create optimized search algorithms. If I'm really looking to quantize the importance of phase relative to magnitude (relative to the consumer, relative to me) then a fuzzy logic algorithm can do it.
Another consequence is that to ensure 100% transmission from musician to consumer (relative to me), at the conclusion of the tests they must both answer Yes to all of the questions and flow through the same test algorithm path. The inherent data of interest to the engineer are the weights required to force the question path to the same conclusion. Those are the minimum requirements of 100% fidelity from musican to consumer relative to the engineer.

Having played in an orchestra or two, a couple of bands and having many musician friends I have found over the years that many musicans are, with a few rare exception, indifferent to the reproduction chain. Many of them will happily listen to a boom box and report that it sounds fine to them. It's all about performance and reproductive accuracy means almost nothing.

The test procedure was not to see what musicans like to hear. It was intended to test what the creating artist wanted to communicate to others. I'ld put money that when it comes to recordings of themselves your friends would be more decerning about the quality of the recording.
How else can you explain how ordinary people desire $$ cameras and HD video cameras when there is no financial gain from the equipment?

I'ld put money that when it comes to recordings of themselves your friends would be more decerning about the quality of the recording.

I've spent some time on both sides of the sound board. For 80%, probably 90%, of the musicians I know you would loose that bet.

I've spent some time on both sides of the sound board. For 80%, probably 90%, of the musicians I know you would loose that bet.

If you told them the recording was for 1. a student,2. a peer, 3. a mentor, 4. a recording company do you think that would affect their concern for fidelity?

And when I lost that bet in terms of fidelity are we talking AM, FM or CD?

If you told them the recording was for 1. a student,2. a peer, 3. a mentor, 4. a recording company do you think that would affect their concern for fidelity?

Don't think it would matter.

And when I lost that bet in terms of fidelity are we talking AM, FM or CD?

Things that would matter would be things like background noise ( eg. outside noises, not equipment noise floors) and maybe room reverb. Other than that, well they'd ask for CD quality, but.... I've seen musicians home systems include mismatched left and right stereo pairs, boom boxes (or slightly better), speakers everywhere but none of them any good (the louder the better rock and roll type guys), you name it.

Don't think it would matter.

that's actually the crux of my logic. the relative information from one observer to the next.
I love photography. The photos which I take and post to family is of inferior technical quality to those I post in photography forums. An email I might send to my peer vs my boss is different. Not just the literal content but the tone, which is another information layer riding parallel to the literal content.



Things that would matter would be things like background noise ( eg. outside noises, not equipment noise floors) and maybe room reverb. Other than that, well they'd ask for CD quality, but.... I've seen musicians home systems include mismatched left and right stereo pairs, boom boxes (or slightly better), speakers everywhere but none of them any good (the louder the better rock and roll type guys), you name it.

Firstly I need it to be clear that the level of fidelity that a musician requires has to be their own material and when the comparison is done it is very preferabley fresh in their mind.
So if this were the playback mechanism of the musician, playing the musicians music, what I interpret is that his mismatched setup meets minimum thresholds to ensure 100% communication transmission back to himself. If I were to replay the recording on a more $ system then the extra quality I hear has nothing to do with his intended communication. It's padding another couple of decimal places when 2 was good enough. And I distinguish this as icing over the cake that I am free to mold and shape as I see fit. In my model this is already outside the realm of fidelity.
And in consideration of the musicians transmission to me it implies that I should be putting more effort into soundproofing the room rather than flattening room reponse.

(Why a musician might want the recording quiet? Just pulling this even deeper from outta my ass but that's how he hears the music in his head even before his lips hit the mouthpiece and that's what he wants to communicate)

Unlike matter/antimatter, unfortunately they don't annililate each other. Thus... the thread still exists. :)

This thread? You don't like this thread?

This thread to me is what AVS is all about, many links, many experts....if people want to learn about measurements and sound this is a good thread for the topic.

I feel sad for those who want to run and hide from the science behind audio, I also never understood why those people are on forums like this period. They should just enjoy their systems.

That is why Harman spent considerable money on a multichannel and in-wall speaker mover -- so the positional biases are removed from the test.

In our listener training exercises, listeners commonly mistake dips as peaks located higher in frequency.

Comprehensive anechoic loudspeaker measurements combined with the right set of in-room measurements can usually explain what you are hearing.

I nominate this for best post of the week.

--Ethan

This thread? You don't like this thread?

This thread to me is what AVS is all about, many links, many experts....if people want to learn about measurements and sound this is a good thread for the topic.

I feel sad for those who want to run and hide from the science behind audio, I also never understood why those people are on forums like this period. They should just enjoy their systems.

The "topic" of the thread is great.

I agree somwhat. This is what the AVS forum should be about. Many links, perhaps a few "experts". Tough to separate the wheat from the chaff though IMO.

I feel sad for those that take some info and want to digest that as "gospel" and run and hide from practical experience/application or personal preference. Period.

I enjoy my system and many others I've auditioned over the years. Personally... I've never been overly critical to actually measure anything. And... that makes my wife happy too. :D

I feel sad for those that take some info and want to digest that as "gospel" and run and hide from practical experience/application or personal preference. Period.

That is strawman argument. Period. :rolleyes:

Not an argument at all... an observation.
The strawman has a brain. ;)

The "topic" of the thread is great.

I agree somwhat. This is what the AVS forum should be about. Many links, perhaps a few "experts". Tough to separate the wheat from the chaff though IMO.

I feel sad for those that take some info and want to digest that as "gospel" and run and hide from practical experience/application or personal preference. Period.

I enjoy my system and many others I've auditioned over the years. Personally... I've never been overly critical to actually measure anything. And... that makes my wife happy too. :D

I really think you are making too many assumptions. For example, I love measurements, I want to know how something is actually better. If it sound better I really want to know why but at the end of the day Im just another guy that loves certain brands, certain looks and will buy based on how something sounds and looks regardless of any measurements. In my room I actually EQ to my own preference, I can do this because I have active crossovers so my speakers can sound different any time I want :D


I think most here can separate all the measurements talk/learning/etc and the pure enjoyment of a speaker or a piece of equipment. The biggest different between you and someone like me is that I really, really try to leave my subjective hat at the door and when Im posting on this forum I hope Im being as objective as I can be. That is hard and I know Im still subjective about things but I try to include the word "subjective" so that there is no confusion.

There is a happy place somewhere in the middle, I love reading about someone's enjoyment of a new amp, processor, speaker, etc but I hate when they use that enjoyment as a tool to try and convince someone else to buy the same product, measurement, data be damned.

I feel sad for those that take some info and want to digest that as "gospel" and run and hide from practical experience/application or personal preference. Period.

Wow, I think I misjudged you. That's a surprising statement coming from you, but welcome!

Measurements are interesting to a point, but to assume they can replace experienced stimulus is a little "off".

We just don't listen using the same parameters used when measuring.

Wow, I think I misjudged you. That's a surprising statement coming from you, but welcome!

Measurements are interesting to a point, but to assume they can replace experienced stimulus is a little "off".

We just don't listen using the same parameters used when measuring.

You are completely out of touch with reality if you think anyone here just uses measurements.

Also, are you here just to make silly comments? If you do not have anything scientific to add could you leave my thread alone? I have not found a post from you that is worthy to read period so less from you in my threads is better for me!

You are completely out of touch with reality if you think anyone here just uses measurements.

Oh, they're on here, trust me. You know who they are.

Also, are you here just to make silly comments? If you do not have anything scientific to add could you leave my thread alone? I have not found a post from you that is worthy to read period so less from you in my threads is better for me!

You don't "own" threads, and certainly don't care if something I say isn't "scientific". That requirement is in your head, and frankly your ego problems won't affect my decision to post one way or the other.

Wow, I think I misjudged you. That's a surprising statement coming from you, but welcome!

Measurements are interesting to a point, but to assume they can replace experienced stimulus is a little "off".

Since 'experienced stimulus' can often be misinterpreted by the 'experiencer', measurements can come in very handy to sort the facts of the matter out from the *imaginary*.

We just don't listen using the same parameters used when measuring.

:rolleyes:

Parameters for *what*?

Audiophile listening 'parameters' may lead one to believe all sorts of nonsensical things. You are of course free to do that...and others are free to call them nonsensical when you post them here.

Parameters for *what*?How about whether or not it sounds good? To YOU. Would that not be the most important "parameter"?

Take 5 "top of the line" speakers of comparable design. Throw them in a anechoic chamber and measure the crap out of them. IMO, it doesn't mean squat once you get 'em home.

Buy what sounds good in your home, to your ears. If one only buys and expects perfection based on "numbers" alone is in for a rude and perhaps expensive awakening. Your home is not the same as a lab and can't expect an apples to apples outcome. OTOH... you can invest XX dollars with sound treatments or whatever to protect your investment/expectations.

How about whether or not it sounds good? To YOU. Would that not be the most important "parameter"?
It might be to you. But it wouldn't have any value for anyone else, because they aren't carrying the same biases into the comparison that you are.

Buy what sounds good in your home, to your ears. If one only buys and expects perfection based on "numbers" alone is in for a rude and perhaps expensive awakening. Your home is not the same as a lab and can't expect an apples to apples outcome. OTOH... you can invest XX dollars with sound treatments or whatever to protect your investment/expectations.
You'd be better off buying your speakers based on measurements, then using your ears to treat your room. Starting with (technically) better speakers will maximize what your room treatments can achieve.

How about whether or not it sounds good? To YOU. Would that not be the most important "parameter"?

There are lots of things that sound good to many people. "Sounds Good" is not an absolute, no matter what many people seem to think.

By now you should have heard someone say that test equipment is far more sensitive than anybody's hearing. There's a consequence of that may make you uncomfortable: There are many things that measure differently, but sound exactly the same to everybody.

Therefore, there are a large number of different things that sound good to you.

If there was something that sounded *best* to you, there are still a great many things that measure out to be different, that would all sound best to you. Or me.

How about whether or not it sounds good? To YOU. Would that not be the most important "parameter"?


Perhaps if you'd finally take to heart the rest of what I wrote -- you know, the part about the instability of judgments using the 'what sounds good to ME' method (i.e., sighted) -- you wouldn't bray like this whenever I suggest shortlisting loudspeakers by the sorts of objective approach you'd probably use for other audio gear.

Said instability is well supported -- if you want a stellar example, look up Sean Olive's (Tonmeister here) story about the audio magazine reviewers who rated a loudspeaker 'Speaker of the Year' by the usual 'what sounds good to me method, but *last* among four competitors, when they were actually able to audition its sound under bias-controlled conditions. (Said loudspeaker didn't measure so hot either.)

Take 5 "top of the line" speakers of comparable design. Throw them in a anechoic chamber and measure the crap out of them. IMO, it doesn't mean squat once you get 'em home.

Sure it does. If the one that measured well in a comprehensive battery sound horrible at home, it could mean your room could use some treatment. Which is almost always the case anyway. The nice thing is that the problem isn't the loudspeakers.

Btw, what do you mean by 'comparable design'? General design (e.g., sealed vs ported vs horn vs electrostatic; bookshelf vs tower)? Or comparable measured performance under the same conditions?

Because if the latter 'doesn't mean squat'; when you bring them home, then you're probably forming a lot of your preference based on something *other* than the differences in sound.



Buy what sounds good in your home, to your ears.

And then if you move, or have to move the speakers -- suddenly, hey, they don't sound so good! Time to go speaker-comparing again! :rolleyes:


If one only buys and expects perfection based on "numbers" alone is in for a rude and perhaps expensive awakening. Your home is not the same as a lab and can't expect an apples to apples outcome. OTOH... you can invest XX dollars with sound treatments or whatever to protect your investment/expectations.

Have you bothered to read *any* of the actual research on these matters?

As you fix anomalies in your room, your formerly great-sounding speakers may end up sounding like the poor performers they really are. That's the problem with loudspeakers that are bought to suit a particular room at a particular time.

Not to mention the biasing influences that could lead to buying really expensive lemons.

The 'buy what sounds good at home' method also ignores the issue of multiple auditions. It's a rather inconvenient prospect for most consumers. How many did you bring home the last time you bought loudspeakers, before you decided on ones you would keep? How did you set up the auditions? Did you keep notes to track your preferences?

Take 5 "top of the line" speakers of comparable design. Throw them in a anechoic chamber and measure the crap out of them. IMO, it doesn't mean squat once you get 'em home.

Buy what sounds good in your home, to your ears. If one only buys and expects perfection based on "numbers" alone is in for a rude and perhaps expensive awakening. Your home is not the same as a lab and can't expect an apples to apples outcome. OTOH... you can invest XX dollars with sound treatments or whatever to protect your investment/expectations.

You are aware that you also proved that audition speakers outside of your home does not mean squat either ;) and if you are not treating your rooms, how can you post online that your speakers sound good at all :eek:

I would rather have my speakers techincally accurate so that I have a better chance of accuracy in my room. I can THEM EQ then to what sound I actually want. I believe this is the more logical way to building a better sound system!

No one has posted what sound is not measureable yet, they post adjectives describing what they think they hear but still everything important can be proven through measurements. Several people accurately posted that great measurements do not exist and that it isnt worth the cost of doing business to do all the measurements but that is only because customers do not demand them they are still stuck with the outdated idea "Just use your ears".

...
Another consequence is that to ensure 100% transmission from musician to consumer (relative to me), at the conclusion of the tests they must both answer Yes to all of the questions and flow through the same test algorithm path. The inherent data of interest to the engineer are the weights required to force the question path to the same conclusion. Those are the minimum requirements of 100% fidelity from musican to consumer relative to the engineer.
This assumes that music is a communications medium between performer and listener. Many artists would disagree with this assumption, and disavow the idea that they seek to transfer what is in their head to the listener's. Rather, they seek to create imagery which is subject to wider perception and interpretation then just their own.

In the latter case, objective transmission of the sound would be the most important thing. That is, minimize noise (in the broadest possible meaning of the term) in the audio channel. Since we don't know what abstracted, subjective features may be important, we should try to preserve everything as faithfully as technologically feasable.

You are aware that you also proved that audition speakers outside of your home does not mean squat either
Absolutely agree

... and if you are not treating your rooms, how can you post online that your speakers sound good at all. Perhaps not everyone has a need or desire to use room treatments. It's a personal choice. My analogy would be... if you own a car and don't use a gas or oil treatment, how could one post that their car runs/performs great?

I would rather have my speakers techincally accurate so that I have a better chance of accuracy in my room.
Good thought. But... what is the definition of a speaker being "technically accurate"? What are the specs/measurements/guidelines?

I can THEM EQ then to what sound I actually want. I believe this is the more logical way to building a better sound system!That's my concern. If you have to EQ and whatever... isn't that a contradiction and doesn't that essentially alter the "technical accuracy" of the speaker.

...but still everything important can be proven through measurements. Measurements are great and could be benificial to the consumer. BUT! Until all speakers are measured/tested using the same criteria, measurement techniques and equipment, it (IMHO) becomes nothing more than a potential for deceptive marketing.

I'd welcome compreshensive measurements from all or most manufacturers. That ain't happening anytime soon as far as I can tell. So, you do the best you can.

This assumes that music is a communications medium between performer and listener. Many artists would disagree with this assumption, and disavow the idea that they seek to transfer what is in their head to the listener's. Rather, they seek to create imagery which is subject to wider perception and interpretation then just their own.

How can they seek to create imagery that they don't know about? This equates performers with, oh, turntables. I don't believe you.

How can they seek to create imagery that they don't know about? Drugs.

Absolutely agree

Even auditioning in your home doesn't necessarily mean squat *about the loudspeaker*. It could mean much more about the you, your room, your biases....

Note that it's not hard to find rave reviews of loudspeakers that measure poorly. Once again, when such loudspeakers are compared fairly to those that measure well, they tend be rated as *poor sounding*.
.

Some here really need to ponder the implications of that, before they recommend the 'just buy what sounds good to you' method..the same method that produced those 'rave reviews'. You're basically saying, since we can't compare speakers fairly at home, we should stick with the method that can easily give us results in direct opposition to those we'd get using a fair method. (And sivad would add an obligatory sneer at the *very idea* of doing it differently)

Sorry, I think there's a better way. It's limited by the paucity of good measurement data , compared to the plethora of choices -- but that only means we should be agitating for more data. It doesn't mean there's NO good candidates out there by objective criteria.

How can they seek to create imagery that they don't know about? This equates performers with, oh, turntables. I don't believe you.
You are confusing artistic imagery with perception.

Even auditioning in your home doesn't necessarily mean squat *about the loudspeaker*.
That's fair... unless "you" don't care or understand about numbers/specs. Most individuals want a 'bang for the buck". You brought up the point. :) But... home audition is better a better selection method (when possible).

Note that it's not hard to find rave reviews of loudspeakers that measure poorly. Once again, when such loudspeakers are compared fairly to those that measure well, they tend be rated as *poor sounding*.
. Anyone can rave about a purchase or personal preference. Some like Big Mac, some like Whoppers. BUT... technically, how does one measure which tastes better or is a better product?

You're basically saying, since we can't compare speakers fairly at home, we should stick with the method that can easily give us results in direct opposition to those we'd get using a fair method.
No... what I am trying to state is that currently, the better method of choosing a speaker is some "up front" homework and a home audition when/where possible.

Sorry, I think there's a better way. It's limited by the paucity of good measurement data , compared to the plethora of choices -- but that only means we should be agitating for more data. It doesn't mean there's NO good candidates out there by objective criteria.

Absolutely, there is a "better" way. But again, until there is a standardized method (certification?) for testing and results for ALL speakers, one is at the mercy of how the product is marketed and how the manufacturer determines how best to sell their product(s).

Great thoughts... but hypothetically, if there were such a standard/cert that every speaker had to meet/achieve, choices would be very limited if buying by "numbers" alone.

So, we should just select a speaker based on a perfectly flat measurement anechoically?

Man, wave good-bye to 99% of all speakers out there.

So, we should just select a speaker based on a perfectly flat measurement anechoically?

Man, wave good-bye to 99% of all speakers out there.

No one said that, you really do not understand what people post :(

Some people can choose a flat measurement others can choose, House curves, Bright curves, Warm Curves.....and so on.

I would suggest people choose the speakers with the best measurements ACROSS the board not just FR plots but In the end people can still choose what they want but everyone should realize that there are lots of measurements that can dictate the performance of speaker.

Anyone can rave about a purchase or personal preference. Some like Big Mac, some like Whoppers. BUT... technically, how does one measure which tastes better or is a better product?

To dumb down Speakers selection to being just a taste like hamburgers is the problem. IMO.

If that is true for some people then they should just buy the most talked about speakers/marketed speakers because that is how they are going to choose anyways.....um BOSE ;)

Absolutely agree

Perhaps not everyone has a need or desire to use room treatments. It's a personal choice. My analogy would be... if you own a car and don't use a gas or oil treatment, how could one post that their car runs/performs great?


I wouldnt post runs/performs great as a fact...I would post SUBJECTIVELY that I like the performance of my car and post some data behind it. Atleast with cars there are numbers to validate opinion.



Good thought. But... what is the definition of a speaker being "technically accurate"? What are the specs/measurements/guidelines?



Good question, Someone posted a great list of measurments somewhere in this thread. To get those would be a great start and yes, there is lots of education needed.




That's my concern. If you have to EQ and whatever... isn't that a contradiction and doesn't that essentially alter the "technical accuracy" of the speaker.



Unperfect rooms need EQing, Auto EQing is to fix room problems. If you have inaccurate speakers, you are essentialy EQing the speakers AND the room....kind of a huge work around if you ask me. Manual EQing, is for when I want BASS, I want a warm sound and so on. Speakers should be accurate so that we can perform then different changes with ease.


Measurements are great and could be benificial to the consumer. BUT! Until all speakers are measured/tested using the same criteria, measurement techniques and equipment, it (IMHO) becomes nothing more than a potential for deceptive marketing.

I agree! The point of this thread isnt to change anything because we all know the truth but Im really interested in figuring out what isn't measurable. Somehow people get offended by threads like this and start cramming the "Why do you let your ears decide" BS down my throat. That arguement is old and like religion never gets anywhere so I just wanted to talk about what measurements can tell us and what can not be measured.

No one said that, you really do not understand what people post :(

I need clarification when people post in an unclear manner. So expect many requests for clarification on AVS.

If we're going to get hung up on measurements, and among those we have the option to choose less-than-flat, what's the difference between that waste of time and simply going to listen? The whole point of looking at measurements at all is to see how close to neutral or "ideal" the speaker is without bias.

I have a feeling that many here would eschew certain speakers as an option if they saw the measurements. Whereas, if they went to listen, they may embrace it as something totally to their taste.

Your approach is say "screw it, I'm EQing anyway", which is another reason to ignore measurements entirely since the end result will be whatever flavor you want it to be anyway.

To dumb down Speakers selection to being just a taste like hamburgers is the problem. IMO.

If that is true for some people then they should just buy the most talked about speakers/marketed speakers because that is how they are going to choose anyways.....um BOSE ;)

Not really. No one is "dumbing down". The fact is that with the majority of the population, no one cares about which hambuger (speaker?) is the healthiest, has the most pickles, better sauce, better bun, better beef, etc.

They want the burger that suits their tastes/requirements at a good price. They don't read (or care about) the nutritional/content information at all. So, just like Bose, they sell more Big Macs and Whoppers than a restaurant that sells Kobe beef burgers (E.G. Martin-Logan).

I need clarification when people post in an unclear manner. So expect many requests for clarification on AVS.

If we're going to get hung up on measurements, and among those we have the option to choose less-than-flat, what's the difference between that waste of time and simply going to listen? The whole point of looking at measurements at all is to see how close to neutral or "ideal" the speaker is without bias.

I have a feeling that many here would eschew certain speakers as an option if they saw the measurements. Whereas, if they went to listen, they may embrace it as something totally to their taste.

Your approach is say "screw it, I'm EQing anyway", which is another reason to ignore measurements entirely since the end result will be whatever flavor you want it to be anyway.


Clarification is one thing but your posts suggest you make your own conclusion (most times they are wrong too).

People should look at the measurements of their speakers, they wont like them for long and that IS a good thing. Education is key to creating the best audio system, there is no way around that.

You call it getting "hung up", I call it "educated ourselves"...I wonder which opinion will help people build a better system! ;)

Btw, I never said screw "it, Im EQing". Im saying that you can not EQ bad speakers/bad room very well. To get a better system you need to choose accurate speakers and EQ them in room to fix room problems then you can make minor adjustments for those specific needs people crave. I have a fully active system myself so my eyes where opened to all the possibilities about a year ago. The joke is that everyone is already EQing inaccurate speakers for no reason, well the only reason is ignorance about audio science.

Not really. No one is "dumbing down". The fact is that with the majority of the population, no one cares about which hambuger (speaker?) is the healthiest, has the most pickles, better sauce, better bun, better beef, etc.

They want the burger that suits their tastes/requirements at a good price. They don't read (or care about) the nutritional/content information at all. So, just like Bose, they sell more Big Macs and Whoppers than a restaurant that sells Kobe beef burgers (E.G. Martin-Logan).

Absolute but I doubt the audience here are the BigMac lovers. The audience for this topic are the people that do want the best possible audio solution in house and you do not do that by going out and finding your favorite in-accurate sounding speakers.

Once again, people can choose to use whatever method they want but everyone with any sort of audio passion SHOULD BE supporting and promoting audio science, audio measurements,etc.

Its a shame to argue against something that will help anyone that chooses to use it. Its a shame that the subjective crowd needs push 'the faith' idea on others. Its a shame that companies want audio ignorance instead of Audio intelligence because they do not have to worry about huge flaws.

Somehow people get offended by threads like this and start cramming the "Why do you let your ears decide" BS down my throat. That arguement is old and like religion never gets anywhere ...

I don't think that people get "offended", but I do think that those that disagree or play the devil's advocate can sometimes come off as being condescending.

I do not disagree that a standardized method of testing/certification for speakers could be beneficial to some, but to many... they won't/don't care. Secondly, the speaker manufacturers probably have the same mentality. If there were strict guidelines/specs/certs to adhere to, there would be a very limited number of speaker selections.

Basically, if anyone wants "technically accurate" speakers, perhaps the best one can do is focus on speakers that have THX certification. :)

I don't think that people get "offended", but I do think that those that disagree or play the devil's advocate can sometimes come off as being condescending.

I do not disagree that a standardized method of testing/certification for speakers could be beneficial to some, but to many... they won't/don't care. Secondly, the speaker manufacturers probably have the same mentality. If there were strict guidelines/specs/certs to adhere to, there would be a very limited number of speaker selections.

Basically, if anyone wants "technically accurate" speakers, perhaps the best one can do is focus on speakers that have THX certification. :)

good points.

I have created "travel to audtion speakers is a waste of time" threads and had to put a flame suit on :D but you make the same general points I made in the past. I agree with you that the majority of people do not care one bit about true measurements and that is cool with me because those people are not on an audiophile website looking for ways to improve their setup.

Of course those who do not care make up probably 95%+ of the market for all companies so its common sense for the companies not to waste $$$ on accuracy, measuring and so on.

None of that is meaningful to me and my persuit to understand what can not be measured and/or what great measurements can be utlized that we know little about.

Clarification is one thing but your posts suggest you make your own conclusion (most times they are wrong too).

You need to point out specifically what was "wrong" about my conclusions, or get lost. I've seen plenty from people that "play house" with their gear with little practical understanding of the principles or applications involved in proper room calibration and speaker integration. Since you happen to be addressing someone that does this professionally, you may choose to shelve your internet bravado for a couple minutes and learn something. At the very least, examine an approach that may put you outside of your comfort zone. that's never a bad thing, unless you're insecure to start with. When someone is simply playing devil's advocate or spurring conversation along and you attack them, I'll assume the latter.

You call it getting "hung up", I call it "educated ourselves"...I wonder which opinion will help people build a better system! ;)

If it's irrelevant, "hung up" is more appropriate. Educating someone one part of an issue is a disservice. I'll put your amateur night education against mine any day, but here's a tip--I make a great living doing this and you don't.

Btw, I never said screw "it, Im EQing". Im saying that you can not EQ bad speakers/bad room very well. To get a better system you need to choose accurate speakers and EQ them in room to fix room problems then you can make minor adjustments for those specific needs people crave.

Wrong. You don't EQ speakers to fix a room. You fix the room first, then dial in the speakers for optimization. Anything else is coloration.

The joke is that everyone is already EQing inaccurate speakers for no reason, well the only reason is ignorance about audio science.

If one thinks that fundamentally altering the sound of a speaker is going to fix acoustic issues--particularly with a push-button EQ--then they're deluded.

You need to point out specifically what was "wrong" about my conclusions, or get lost.

Get lost??

Lol, this is my thread. If anything maybe you should not be involved with the discussion. I ask you once to leave but you seem to think you are important enough to stay :eek:

Of course I keep responding to you so shame on me. You offer nothing in terms of science so if you could just move on it would help keep the thread on topic.

The rest of your post shows you are just a troll, please leave!

Get lost??

Lol, this is my thread. If anything maybe you should not be involved with the discussion. I ask you once to leave but you seem to think you are important enough to stay :eek:

Of course I keep responding to you so shame on me. You offer nothing in terms of science so if you could just move on it would help keep the thread on topic.

The rest of your post shows you are just a troll, please leave!

http://www.scottwax.com/rice/videos/smilies/whine.gif

shame on you is right

Most people here do not care to have "scientific" data thrown at them; and that's true in person as well. The only ones that do are the Google scientists here that engage in such talk for mutual masturbation purposes.

http://www.scottwax.com/rice/videos/smilies/whine.gif

shame on you is right

Most people here do not care to have "scientific" data thrown at them; and that's true in person as well. The only ones that do are the Google scientists here that engage in such talk for mutual masturbation purposes.

Most people are uneducated and very ignorant about many, many things. I have little need for people like that.

This is a thread to discuss science, I want it to stay at a decent level of intelligence and also I do not want the attacks subjective crowd always takes it down too...(you are a perfect example)

If science isnt your thing then just ignore science threads.....finally once again just move on.

This is where I get off the bus... sorry penngray. I thought we had a civil discussion going (for once ;) ) but unfortunately, the condescending comments from some individuals says it's time to say buh-bye (before I wind up getting myself in the "time-out" chair again).

Most people here do not care to have "scientific" data thrown at them; and that's true in person as well.

I suppose you believe "most people here" prefer to have unsubstantiated nonsense "thrown at them" instead??

At the risk of returning to the subject of the original post:

I think it has been said already, but it may not be so much what can be measured as what actually is measured. Speakers and amplifiers are measured for frequency response using a series of single tones. That is not what we listen to. Amps are measured for distortion using a single, static tone. Even IM distorition is measured only with a single pair of closely spaced tones (typically 19K+20K). Real music, voices and sounds are far more complex than that.

I want my electronics to at least meet, and hopefully exceed, their manufacturers' rating when tested by a third party. Makes me feel good about their engineering. And I pay attention especially to the IM distortion ratings. I assume that an amp with a lower IM distortion rating, and a cleaner IM spectrum, will perform better than an amp that does worse in that test, when both are called on to reproduce real world signals consisting of dozens if not hundreds of separate tones (counting overtones) all attacking and decaying at their own individual rates. But it merely an assumption - - I don't know for sure. Neither do I know whether, in a real world situation, one amp's distortion signature is more benign than another's (i.e. more even-order, and low even-order at that harmonics, which may be more readily masked, and more, um, harmonious than odd-order harmonics)

None of this touches other issues like phase shift, which, as I understand it, can be audible. I've never heard a demonstration that shows me what a signal with certain frequencies phase-shifted sounds like, so I don't know. I assume that phasing issues are part of what make recorded sound seem unnatural (i.e. you can tell it's a recording, not a guy standing in front of you talking). Nor have I addressed energy storage in speaker cabinets, etc, which you can see on speaker test waterfall plots, and which may not be revealed by a speaker's frequency response, at least as typically measured. BUt at least you can find measurements for some aspects of those things.

But distortion in speakers is roundly ignored, although I have always seen anecdotal asides that indicate it probably is significantly higher than electronics distortion. How accurately a speaker responds to a series of single-note sine waves may not tell you whether, when given a much more complex input, its distortion signature collects harmonics in the lower treble/high midrange presence region. That could make a "flat" speaker sound bright.

I wonder whether it would actually be possible to run a test using a music signal, or a soundtrack, and compare the waveform going in with the waveform produced by the device (amp or speaker). You would think that with adequate computing power you could correct for microphone or other testing equipment anomalies as well as for the relative levels, then just compare the two, and see how close they are. Instead we have tests that are stand-ins for the real thing and have to assume that they give us enough information to at least begin with. Maybe it's been done and I just don't know about it. It's certainly not my area of expertise.

I like measurements. I just don't think the measurements we get tell the whole story. There are probably numerous other sound-related issues I have not thought of. One that may not be quite so important to me is a speaker's ability to reproduce the very leading edge of transient sounds (like the roughly 0.02 second first hit of a snare drum rim shot, which may be 10 db or more above the "main" sound of the shot). At least one aftermarket guitar speaker manufacturer describes this quality (or somethin like it) as "agressive" in response to pick attack, etc. Guitarists choose their speaker in part based on whether they want that aggressive response, or something that smooths out those bumps. For our purposes, I think we'd ideally want a speaker that can reproduce those brief leading edges fully and accurately. But I suspect that most speakers can't do it, and we live more or less contentedly with our smoother sound. (Of course this assumes that your soundtrack or music hasn't had the peaks leveled off too much through compression. If it's highly compressed, you still have the very short duration, but not the huge swing in terms of relative sound pressure level . . . )

This is where I get off the bus... sorry penngray. I thought we had a civil discussion going (for once ;) ) but unfortunately, the condescending comments from some individuals says it's time to say buh-bye (before I wind up getting myself in the "time-out" chair again).


Ratman, sorry to read you do not want to discuss. I enjoyed reading your opinion on this. We actually agree more then you think but we are looking at things differently and I believe we are focusing on different audiences.

I suppose you believe "most people here" prefer to have unsubstantiated nonsense "thrown at them" instead??

Pretty sure no one asserted that position either.

People want info they can use. At the end of the day, if we are going stress the importance of measurements, then turn around and say that's it's OK to "look for house curve results" (which negate the need to look at measurements at all), it's all kind of moot.

Penn took issue to anyone daring to question his omnipotence on "his thread" (rofl) and as usual that's where the discussion broke down. Asserting that someone is always getting confused and is generally wrong will tend to do that, but that's expected from him.

I think it has been said already, but it may not be so much what can be measured as what actually is measured. Speakers and amplifiers are measured for frequency response using a series of single tones. That is not what we listen to. Amps are measured for distortion using a single, static tone. Even IM distorition is measured only with a single pair of closely spaced tones (typically 19K+20K). Real music, voices and sounds are far more complex than that.

You'll never get any traction with that here. It's too logical, and dares to take personal preference into account during the speaker selection process.

I like measurements. I just don't think the measurements we get tell the whole story.

Of course they don't. Good luck with stating the obvious with certain folks here.

Pretty sure no one asserted that position either.

People want info they can use. At the end of the day, if we are going stress the importance of measurements, then turn around and say that's it's OK to "look for house curve results" (which negate the need to look at measurements at all), it's all kind of moot.


Just as you could seek loudspeakers that are *inherently* accurate as indicated by a suite of measurements, you could, if you wanted to , seek loudspeakers that are *inherently* nonlinear with any shape of curve you desire -- 'house curve' (elevated bass, depressed treble), smiley-face (boosted bass and treble), or even ones with amusingly bodacious notch-like filtering like the $4000 Zen Druids. I personally wouldn't go that route, any more than I'd buy a CD player that purposely acted as permanent smiley-EQ equalizer, but hey, it takes all kinds.


Penn took issue to anyone daring to question his omnipotence on "his thread" (rofl) and as usual that's where the discussion broke down. Asserting that someone is always getting confused and is generally wrong will tend to do that, but that's expected from him.

And your clown act is hardly less predictable. It's particularly amusing that you recently started a whiney thread (http://www.avsforum.com/avs-vb/showthread.php?t=1130690) proposing that moderators shut down 'nasty fest' cable threads because you were so worried that an 'OP that really wants to glean real data', doesn't get a chance to.

And here you are adding all noise, no signal, to an OP's --penngray's -- data-seeking thread. :rolleyes:





You'll never get any traction with that here. It's too logical, and dares to take personal preference into account during the speaker selection process.

You're too obtuse to attempt sarcasm successfully.


Of course they don't. Good luck with stating the obvious with certain folks here.


Funny how what's 'obvious' to certain folks doesn't stop actual researchers from testing the relationship between measured performance and listener preference....

You're hopeless, so I'll ask JHaz: JHaz, are you at all familiar with such research? Are you aware, for example, that actual music, not test tones, is used in the listening part of the studies?

At the risk of returning to the subject of the original post:

I think it has been said already, but it may not be so much what can be measured as what actually is measured. Speakers and amplifiers are measured for frequency response using a series of single tones. That is not what we listen to. Amps are measured for distortion using a single, static tone. Even IM distorition is measured only with a single pair of closely spaced tones (typically 19K+20K). Real music, voices and sounds are far more complex than that.

Um, you're completely wrong, but other than that.

1) Speakers and amplifiers are measured in a number of ways, including, but not limited to, a series of single tones. Sweeps, for example, are not single tones. Noise tests are not single tones. MLS is not a single tone. Nearly none of the modern techniques are a single tone.
2) Amplifires are measured for distortion using impulses, single tones, tone clusters, "buzz tones", and some other methods, too numerous to mention. Very few measurements are 'single tone'.
3) IM distortion, likewise, which is nothing more than another facet of harmonic distortoin, is measured in a vareity of ways. Forget the old IHF methods, they are from before I was born, and dude, I ain't young.
4) Real music, voices, and sounds are comprised of a sum of sine tones, no more, no less. As such, they are no more or less complex than an MLS signal, noise signal, etc. In fact, all physically realizable signals are made of nothing more than a specific sum of sine tones. Google "fourier analysis" for more information on that.

Now, the usually REPORTED measurements are crap. On that we can agree.

... and dares to take personal preference into account during the speaker selection process.

That's interesting, perhaps you could respond to the post above where I said as much?

The very confused, completely wrong bits about sine tones, on the other hand, are not well taken, see my previous post.

Now, "usually reported measurements"... See the article above this.

We can do all sorts of in room or outside measurements to accurately define a speaker. Correct?

Then why do people still ignore all those measurements and use "How does it sound to you" Mantra.

Does accurate speaker equate to best measured speaker? (Flat FR plot, etc)

If the goal is accuracy for some people then why don't they use the measurements instead of the flawed "How does it sound to you" appoarch?

How it sounds to them has little to do with accuracy most times. I have to believe people just think there is a missing measurement out there and therefore they have to listen.

Obviously, Im assuming accurate measurements....yes manufacturers can lie!! Lets assume a speaker has the measurements you want. Why not buy it based on those?

I think measurments should be used much more, research indicates that some types of measurements have very good correlation with peoples judgement of sound quality (in blind tests), bass extension, and flat uniform frequency-responce on and off axis (roll off at higher frequencies of axis though) consitantly seem to rate very high on blind tests. If proper measurments of this kind where available I would at the very least use those to pick out a few alternatives, listen to those, and make my choice among them.

The amount of stupid claims and horrible products in the (home) audio-world is quite disappointing, it is a field the needs much more scientific backing, audio is not magic.

AtW

A sweep is a single tone at a time. Certailny not as complex as a "real sound." To my mind, the difference between a sweep and single tones is basdically not stopping between the tones.

I am confident I said I don't know if there are other tests that I have not seen, but I'll stand by my statement that I have not seen them.

While I tend to agree that IM is probably related to THD, the reason people started doing IM as I understand it is because early in the solid state revolution, people were making amps that measured beautifully on THD and had high power bet did not sound good. They were engineered to deliver great THD results, but had awful IM. As soon as somebody tumbled to the problem and started testing for IM, engineering of amps improved. Isn't that what we all want? Things to improve? To a certain extent, you get what you measure for, and cannot assume that the engineers at a particular company did not shortchange an important design/performance item to maximize performance on the measured tests. (Chinese dog food, anyone? - - I know it's a bad analogy but the concept fits - - make the product meet the spec, even if you aren't accomplishing what the spec is intended to measure).

I don't know what an MLS input looks like, so I'll defer. My point was simply that the more harmonics you get going, the more distortion may be audible (and , I assume - - yes I know it's an assumption) measurable. Easy to hear if you plug a guitar into a tub amp that's cranked to distort a bit. One note, especially a relatively high in pitch note, may not sound very "crunchy" lower notes may sound pretty crunchy along, but play a classic power chord - - easy harmonics, bypically 1-5-1 are the notes - - and the level of audible distortion really umps up. It's hwy, for me, if I have an amp set for relatively scorching lead tone, I have to back off the volume (lower the input level) to reduce the distortion to a point where chords are recognizable. Because I like to use chords that are significantly more complex than just root and fifth, and things can get start to sound very muddy. While I recognize that transistors clip differently, a again assume that a similar thing happens at levels that are far below massive clipping levels that I use with guitar amp. More notes, more distortion. It can't be added level, I don't think, because after a couple or three notes, you're just not adding much input power for each additional note, relatively speaking. Two notesmight be 3 db higher than one, but notes are definitely not 3 db higher than 2, and I rather suspect bhat by a four-tone cohord, you're just not adding anough power to the input signal to make a difference.

While I understand the concept that all sounds can be represented by a series of sine waves, I've never fully wrapped my head around whether that's what the "natural" sounds are, or just a way to represent them reasonably accurately. Stepping away from the natural, when an old school synth puts out a saw tooth or square wave, does the electronic wave not look like a saw tooth? Ah, well, that's an imponderable I've not thought about in a long time . . .

To the extent that there are tests in existence that we don't see, we can't use them to evaluate products or to make purchasing decisions. So the tests we do see are, to my mind, incomplete, and may not tell the whole picture. Which is all I was trying to say.

While I understand the concept that all sounds can be represented by a series of sine waves, I've never fully wrapped my head around whether that's what the "natural" sounds are, or just a way to represent them reasonably accurately.
I would really encourage you to further study on this matter. It is such a fundamental concept that it is hard to evaluate anything in sound measurement without this understanding.

Regards,
Terry

Penn took issue to anyone daring to question his omnipotence on "his thread" (rofl) and as usual that's where the discussion broke down. Asserting that someone is always getting confused and is generally wrong will tend to do that, but that's expected from him.

No, anyone can question if they have a valid question. Many, actually have but your posts are simply looking for a fight and if this was bar I would have zero problems with a true fight since Im Canadian and I played hockey for years, Canadian Hockey players love a good fight :cool:

If you have valid questions then asking them but so far you do not have valid questions, you just have subjective statements and that is not what the thread is about so respect the thread please!

Keep on topic, do not insult and we have no problems. I have researched your posts and I know your MO already!

Speakers and amplifiers are measured for frequency response using a series of single tones. That is not what we listen to. Amps are measured for distortion using a single, static tone.

JHaz, those are false statements. Have you ever performed in room tests yourself.

Im no expert but I have all the hardware software available and I can tell you that when I do any sort of testing its not single tone testing. Different packages (TrueRTA, ARTA, REW) do different things. Is it live music? Of course not but its better then individual songs because the sweeps used are looking at not only frequency response but other things like Decay, etc. Music actually is inadequate for testing.

Now I can measure Movies or Music if I choose too. There is spectrum analysis software that many on this site use to post pretty waterfall plots, etc to show specific movie scenes and how low they go, etc.

sweep is a single tone at a time. Certailny not as complex as a "real sound." To my mind, the difference between a sweep and single tones is basdically not stopping between the tones.

They are more complex actually. Also, "real sound" compared to "Fake sound"? ;) I guess you mean normal music/movies vs Measurement sweeps? Measurements sweeps are as "real" as music/movies, I would go further to state that measurements sweeps are a "more accurate" tool for measuring then snips from music/movies that will never cover 100% of the frequency range.

By real sound I mean not recorded sound. The sound of a person speaking in the room. The sound of a piano playing in the room.

It is one thing to measure your room, etc. and another thing to compare that measurement to the original input. That's the thing I'd like to see. Does the speaker accurately output the complex waveform it is fed, or does it add harmonics of its own? From looking at Mr. Nousaine's measurements of subs, it is clear that speakers distort. From my guitar experience, I know that different speakers distort differently in a guitar cabinet (but it's a dfferent thing - - they are "supposed to.")

Sorry, I'm just not buying that a sine wave sweep is as somplex as a three note chord on a piano. We can agree to disagree. Or not.

As far as I know, people didn't even think about the Fourier transform in measuring or designing audio equipment until digital came along, when we needed a way to demonstrate that you could sample and digitally capture a signal in a way that would reflect the original signal. So while I'm sure that a deeper understanding of it could be helpful, it's just not something I'm inclined to do given the limits on my time. Audio engineering is not what I do.

But I still wonder whether a synth set to put out a sawtooth wave puts out a sawtooth wave. "if a tree falls in the forest, does it emit a series of sine waves?" This is almost just idle curiosity for me. I can still recall the differences between the sounds of the waveforms marked sine, square and sawtooth on the old Moog (maybe it was an Arp) that I had access to at college. But I never saw visually what those outputs really look like. So I'm just curious.

I don't have any sophisticated equipment. Just a cd with third octave warble tones and the good old radio shack spl meter. I'm fairly flat in-room, considering my goofy room shape and lack of treatment - - plus or minus about 3.5 from 25 to 1200 (excepting a troublesome bump at 100 that I ascribe to a room node - - you can see it at 50 hz, too). Dropping off above 1200. In the bass, I am surprised and pleased to say I'm plus or minus 1.5 db from 25 to 200 (except for the pesky 100 hz bump, 50hz is okay the way I'm currently configured) and at 20hz I'm minus another couple -three db, if you trust the conversion factors for the meter. For what it's worth, this is with speakers (magnepan 1.6s) that measure horribly. But the big bass bump in a psuedo anechoic measurement of Maggie is engineered to be there so that you get some bass extension despite the cancellation that occurs because of the dipole behavior. On some program material the system sounds a tad bright, and as I recall i have a rise in the brightness area, which i suspect is as much due to the reflected "back wave" as the direct radiation. I've tried sticking some Auralex behind the speakers, though, and couldn't tell a real difference. One of these days, I want to work on attempting to treat the room (our living room) but I have very severe WAF limits. As do many of us.

All of which is kind of why I am interested in the whole Audyssey thing. If Audyssey gives me half a loaf versus the proper treatment I can't do, it could be worthwhile. But right now, I don't plan to spend the bucks.

All in good fun, eh?

By real sound I mean not recorded sound. The sound of a person speaking in the room. The sound of a piano playing in the room.


I get your point but I think this discussion has little to do with the live sound of a piano in an actual room ;)

Only because speakers do not replace that, they never could and never will.

We can talk about piano playback through speakers and I still believe (until proven other wise) that we have enough measurements out there to prove which speakers plays back the sound of a piano accurately.

I get your point but I think this discussion has little to do with the live sound of a piano in an actual room ;)

Many publications and audiophiles assert that reproduction of "live sound" is always the goal.

Only because speakers do not replace that, they never could and never will.

We can talk about piano playback through speakers and I still believe (until proven other wise) that we have enough measurements out there to prove which speakers plays back the sound of a piano accurately.

Well the answer is none of them do. It's always a reasonable facsimilie, but never the truth.

So then we go back to which sound is preferred. It's circular...

We as humans always judge accuracy based on a real-world reference. This is especially true with voice. Piano, guitar, etc are well-known references to most anyone interested in music, and certainly those that are familiar with live reproduction.

I suspect whether a microphone "think something sounds real", or it looks good on paper is good enough for some people.

Oh an Penn, as for the hockey comment, I'll leave you with this thought: My blocker + your chicklets = good time for all

Well, I think we've reached the point of everybody standing on their own views, which I think is fine.

For those interested, I did find sort of an answer to my sawtooth wave question. Wikipedia contains a discussion of the sawtooth wave form with a visual depiction of creation of a sawtooth from a sine wave by adding a series of 25 harmonics. http://en.wikipedia.org/wiki/File:Synthesis_sawtooth.gif
Fascinating to see. You will see that the additive synthesis (Fast Fourier Transform) wave is not exactly like the sawtooth behind it, but it's cool to see how close it comes, and how the shape changes as harmonics are added. Could you hear the difference between the FFT/additive synthesis waveform and a "real" sawtooth? I don't know. Did a minimoog ever put out e perfect sawtooth form? My guess is not, but I'd imagine the errors are more in the shape of the rise time (not as straight a climb, but not so much the little wiggles along the line. The overshoot at the peaks could well be present in the synth, or not. Anyway, I thought it worth sharing for those who might be interested.

And I still think that without real dostortion measruements, phase information and probably a bunch of other stuff I'm not thinking of, for speakers you don't have enough information to know whether a speaker accurately reproduces the signal generated by recording a piano in a room. If those kinds of data were published, I'm sure we'd have arguments over which were most important: phase errors? At what level? In what frequencies? Distortion? At what level? What's the frequency spectrum of the distortion?
Time errors (this relates to phase, but also takes into account the inability of the "spring" that is a speaker's surround and voice coil to stop immediately when a signal (or part of the signal) stops. How much slop is needed before it becomes audible? Is a speaker with tighter time domain response but less flat frequency response better? In a perfect world, they'd be perfect in every way. But they're not. Even a simple 2-way cone driver design has phasing issues in the crossover range at least, sonce the crossover components themselves change the phase of the signal that passes through them . . . .

Maybe some people are more sensitive to some of these things than others. After years of people saying ultrasonic (above 20khz) sound can't be heard so it can't be important at all, it turns out that some studies show that at least some people can hear the way the ultrasonic "sound" interacts with the audible sound - - so the ultrasonics make a difference to them. Me? I'm not convinced it would make a significance difference to my old ears, and I'm not inclined to start chasing after ultrasonic performance given the other deficiencies in my merely mortal audio reproduction chain. But that doesn't change the apparent fact that the "inaudible" (on its own) apparently can become audible when it interacts with other sounds.

Have a great day, all. Thanks for the interesting discussion.

Sorry, I'm just not buying that a sine wave sweep is as somplex as a three note chord on a piano. We can agree to disagree. Or not.

As far as I know, people didn't even think about the Fourier transform in measuring or designing audio equipment until digital came along, when we needed a way to demonstrate that you could sample and digitally capture a signal in a way that would reflect the original signal. So while I'm sure that a deeper understanding of it could be helpful, it's just not something I'm inclined to do given the limits on my time. Audio engineering is not what I do.

But I still wonder whether a synth set to put out a sawtooth wave puts out a sawtooth wave. "if a tree falls in the forest, does it emit a series of sine waves?" This is almost just idle curiosity for me. I can still recall the differences between the sounds of the waveforms marked sine, square and sawtooth on the old Moog (maybe it was an Arp) that I had access to at college. But I never saw visually what those outputs really look like. So I'm just curious.

I can understand not wanting to take the time to learn the math and physics so I guess you're going to have to take it as a matter of faith, but I will give a shot at some explanation: from a physics POV there is no difference between a set of summed since waves and any other wave form when it comes to the capabilities of the human ear. For audio the exceptions to this rule lie in things like nuclear explosions and the like which are simply not be relevant to normal human experience (if you actually encounter one the exceptions you will most surely be dead afterwards!). This form of analysis isn't something that was recently discovered and predates digital audio, the basics of harmonic analysis have been around since the 1800's...

Electrically, you can produce a sawtooth as a linear change in voltage. When this get's reproduced via a loudspeaker that is now pretty much irrelevant; the resultant waveforms that are created are for a human, identical to a series of summed sine waves. Consider a three way system reproducing a low frequency sawtooth; some portions of that output will be coming from each driver. This is an artifact of the loudspeaker in question, but perhaps the image of how this is happening might help you see how the sine wave summation works physically?

What really matters, is that the information processing bandwidth of the physical and brain systems are the limiting factor on what you can resolve. When you think about it you've got to start wondering how the information would be processed inside the brain and how the brain could possibly process
a continuous linear sawtooth vs. a series of summed sine waves? Things like the reaction time of calcium signaling channels start to predominate. These are physical processes and we can determine the limits for them. Having done so, you can work backwards and figure out what the limits are on the requirements for audio reproduction. JJ can tell you of some interesting grey areas when it comes to CD quality digital signals, but for the most part the reproduction chain that comes before the speakers and the room there really aren't any issues.

JHaz, instead of investigating sawtooths on Moogs (a reproduced sawtooth, like a square wave, will sound the same as the original, as long the frequencies in the audible band are accurately preserved -- just as our ears turn 'square waves' into something not square by virtue of being lowpass filters), how about investigating what test signals are actually used for loudspeakers -- for example, do you think noise is a 'simple' signal compared to a triad on a piano? Have you investigated what MLS is?


And, finally you still don't seem to recognize that the studies that *correlate* test signal-based loudspeaker performance with listener preference, use *music* during the listener preference part.

And I still think that without real dostortion measruements, phase information and probably a bunch of other stuff I'm not thinking of, for speakers you don't have enough information to know whether a speaker accurately reproduces the signal generated by recording a piano in a room. If those kinds of data were published, I'm sure we'd have arguments over which were most important: phase errors? At what level? In what frequencies? Distortion? At what level? What's the frequency spectrum of the distortion?
Time errors (this relates to phase, but also takes into account the inability of the "spring" that is a speaker's surround and voice coil to stop immediately when a signal (or part of the signal) stops. How much slop is needed before it becomes audible? Is a speaker with tighter time domain response but less flat frequency response better? In a perfect world, they'd be perfect in every way. But they're not. Even a simple 2-way cone driver design has phasing issues in the crossover range at least, sonce the crossover components themselves change the phase of the signal that passes through them . . . .

A lot of studies have been done on how humans perceive things like absolute and relative phase errors, various levels of distortion etc. Pretty much every aspect of the human ability to perceive sound has been studied all the way down to the molecular and brain stimulus level. I don't have time to point at them at the moment but there are other threads where this issue has been dealt with ad nauseum (as per standard AVS tendencies to beat this kind of subject senseless).

Maybe some people are more sensitive to some of these things than others. After years of people saying ultrasonic (above 20khz) sound can't be heard so it can't be important at all, it turns out that some studies show that at least some people can hear the way the ultrasonic "sound" interacts with the audible sound - - so the ultrasonics make a difference to them. Me? I'm not convinced it would make a significance difference to my old ears, and I'm not inclined to start chasing after ultrasonic performance given the other deficiencies in my merely mortal audio reproduction chain. But that doesn't change the apparent fact that the "inaudible" (on its own) apparently can become audible when it interacts with other sounds.

Not sure what you are referring to here? If you are referring to audio reproduction via ultrasonic wave interference you have to understand that there is no human capability to hear above 20kHz involved in this process, nor is there any implication as to requirements for audio chain bandwidths required above these limits. Rather, think of this in terms of hitting a long rod with a series of lots of little inaudible taps until you get to the point that you've got the rod vibrating at some fundamental frequency that you can hear. The rod in this case, happens to be a volume of air... (Yes, I know it's not a great analogy, but it's all I have time for at the moment).

Well, I think we've reached the point of everybody standing on their own views, which I think is fine.

For those interested, I did find sort of an answer to my sawtooth wave question. Wikipedia contains a discussion of the sawtooth wave form with a visual depiction of creation of a sawtooth from a sine wave by adding a series of 25 harmonics. http://en.wikipedia.org/wiki/File:Synthesis_sawtooth.gif
Fascinating to see. You will see that the additive synthesis (Fast Fourier Transform) wave is not exactly like the sawtooth behind it, but it's cool to see how close it comes, and how the shape changes as harmonics are added. Could you hear the difference between the FFT/additive synthesis waveform and a "real" sawtooth? I don't know. Did a minimoog ever put out e perfect sawtooth form? My guess is not, but I'd imagine the errors are more in the shape of the rise time (not as straight a climb, but not so much the little wiggles along the line. The overshoot at the peaks could well be present in the synth, or not. Anyway, I thought it worth sharing for those who might be interested.

And I still think that without real dostortion measruements, phase information and probably a bunch of other stuff I'm not thinking of, for speakers you don't have enough information to know whether a speaker accurately reproduces the signal generated by recording a piano in a room. If those kinds of data were published, I'm sure we'd have arguments over which were most important: phase errors? At what level? In what frequencies? Distortion? At what level? What's the frequency spectrum of the distortion?
Time errors (this relates to phase, but also takes into account the inability of the "spring" that is a speaker's surround and voice coil to stop immediately when a signal (or part of the signal) stops. How much slop is needed before it becomes audible? Is a speaker with tighter time domain response but less flat frequency response better? In a perfect world, they'd be perfect in every way. But they're not. Even a simple 2-way cone driver design has phasing issues in the crossover range at least, sonce the crossover components themselves change the phase of the signal that passes through them . . . .

Maybe some people are more sensitive to some of these things than others. After years of people saying ultrasonic (above 20khz) sound can't be heard so it can't be important at all, it turns out that some studies show that at least some people can hear the way the ultrasonic "sound" interacts with the audible sound - - so the ultrasonics make a difference to them. Me? I'm not convinced it would make a significance difference to my old ears, and I'm not inclined to start chasing after ultrasonic performance given the other deficiencies in my merely mortal audio reproduction chain. But that doesn't change the apparent fact that the "inaudible" (on its own) apparently can become audible when it interacts with other sounds.

Have a great day, all. Thanks for the interesting discussion.

Pretty quick to make false conclusions. You have realize some of the posts here are from the experts in the field so I would think its foolish to just agree to disagree and run away because someone posted you have inaccurately concluding something.

Put it to you this way, its been proven time and time again that our ears are not very accurate at all. We can not hear distortion as well as we think, we can not hear nulls in the frequency range as well as we think and so on. Heck we do not even need to touch on how the brain controls our hearing and how we process sound...that is a whole different world of uncontrolled inaccuracies.

So when you talk about using just ears to determine the accuracy of something I cringe because ears are a horrible tool to use for that purpose. If someone is reading this thread and posts in this thread I would have to believe they are searching for accuracy. Why else post or read it?

So then we go back to which sound is preferred. It's circular...

We as humans always judge accuracy based on a real-world reference. This is especially true with voice. Piano, guitar, etc are well-known references to most anyone interested in music, and certainly those that are familiar with live reproduction.



The design method would be to find the accurate speaker and then tweak it in room to your preference (if tweaking is needed at all) .

Its not circular, its just a fact that measured accuracy leads to a better solution long term. People take years to understand this through just listening.

If more people just realized the measurements available can help them a great deal then there would be pressure on the companies to perform more measurements. That would have significant impact on the industry overall (IMO).


Correct me if Im wrong but you do not give a damn about measurements, nor do you care if companies are pressured into provided more of them? Im just trying to figure out what goals you have when you post in this thread.

Correct me if Im wrong but you do not give a damn about measurements, nor do you care if companies are pressured into provided more of them? Im just trying to figure out what goals you have when you post in this thread.

I figured you'd come to the wrong conclusion about about my stance. Something about bias and all that...

I absolutely care about measurements. How could I not? I take pause when some say to pay attention to them, but excuse the practice of actively looking for less-than-flat results. Is that not counter-productive? Could we not EQ from a flat response to something more suitable? Of course, and in most cases we should, since not every room will respond the same way. To start with something less than flat is making one's work harder, and will doubtlessly introduce interesting artifacts. This changes though when one is simply pulling a speaker out of the box with little to no EQ.

It's also problematic when we assume that the measurements will, if it fits one person's requirements, will be a universal template to all.

Sometimes people forget this is an A/V industry. Implied in that is the need to market to a broad set of individuals. Flat is not the sole market. In that case, measurements aren't really all that relevant, since the people that care little about room treatments are also less likely to pay attention to room plots. All they know is their "receiver calibrates the room with a button push".

So am I playing both sides of the fence? Absolutely. It's called being realistic vs. dogmatic.

The market for a treated, professionally calibrated system is only part. For what I would estimate is the remaining 90%, what sounds good is what matters. Even ID speaker companies know that "listening through white papers" is not the whole story, hence their liberal return policies.

I need to post shorter posts so people have less opportunity to read things into what I said. I did not say that one's ears are more accurate. I did say that, apparently, some people can hear (the effects of) things that had been considered unimportant because they are (by themselves) inaudible. People hear what they hear. So once upon a time, somebody was saying "it sounds different when the above-10k information is reproduced," and somebody was saying "you can't hear anything above 20khz, you must be nuts." They were talking around each other in a way - - each was correct. You can't hear a 30 khz sine wave, but maybe some people hear a different sound whtn the 30 khz signal is included with the audible stuff.

Took a moment to look at MLSSA a little closer, but did not dig anto any detailed stuff. If it works like I now understand it does, it looks like it should be a reasonable substitute for a "real" (versus single tone) signal. At least as good, if I understand it right, as any single "real" (ie music or soundtrack) signal is likely to be.

Does everybody use MLSSA to measure their speakers? How do we kinow what method a manufacturer used to measure? Or do we only trust measurements by third parties? Who publishes the kinds of 180 degree soundfield frequency response analyses that were being discussed earlier? How many speaker manufacturers give us impulse response or step response info?

I still only see THD measurements in Mr. Nousaine's sub reviews, not in non-sub reviews, but I haven't dug around deeply for them. I would not take that to mean that non-subs don't distort. I know some speakers distort. In the guitar world, some guys like speaker distortion. I don't. I proved that to myself by playing my tube amp, pushed well into clipping, plugged directly into my mighty clean JBL PA speakers. Sounded great to me. But I cut my teeth on a 15-watt Fender deluxe Reverb with a JBL in it. I surely did not distort that JBL (although I did eventually blow it playing bass through the amp and it never sounded the same after it was reconed but that's a story for another day). I don't need any more added cone distortion, but there are players who love that sound whose work I love. Horses for courses, but when you're creating the noise rather than reproducing it, it really is a different world. My point is simply that speakers sho' 'nuff can distort. So why don't we more routinely measure their distortion?

Measurements always, I think, raise the issue of audibility of any measured inaccuracies. Surely the levels of amp distortion most modern solid state devices exhibit when tested within their limits are inaudible, if you were listening to the test signal. But if the measurements are incomplete in some way, there remains at least the possibility of the converse - - hearing an inaccuracy that has not been measured. And fwiw, I still think a signal like MLS or a simple three note chord on a piano is more complex, offering greater opportunity for harmonic distortion by a speaker (or an amplifier), than a single-frequency sine wave at the same power. Otherwise, why measure IM? And, as I think I said clearly above, I am a big fan of IM measurements - - an electronic device that can handle that 19K +20K torture test with spuriae at -70 or -80 db, I think, just has to be cleaner with any other signal. BTW I don't ever want to listen to that particular signal. But I simply recognize that I am making an assumption that the IM test predicts what happens with more complex signals. I'm happy with my assumption for now . . .

I failed to follow my own advice in my first sentence. Flame away.

You can't hear a 30 khz sine wave, but maybe some people hear a different sound whtn the 30 khz signal is included with the audible stuff.

No, absolutely not. Go back and reread what I previously wrote to you.

I figured you'd come to the wrong conclusion about about my stance. Something about bias and all that...

You noticed that I did post "correct me if Im wrong"

Put it to you this way, its been proven time and time again that our ears are not very accurate at all. We can not hear distortion as well as we think, we can not hear nulls in the frequency range as well as we think and so on. Heck we do not even need to touch on how the brain controls our hearing and how we process sound...that is a whole different world of uncontrolled inaccuracies.



Frankly, the more i read about the auditory system (i try to use that word, since the brain is a big part of how we hear), the more impressed I am with the incredible performance it can have in manu situations. That beeing said, for some thing the auditory system is not very good (or is easily fooled, or whatever you want to call it), and I certainly have little faith in all the strange claims about what humans can hear. And frankly i get a little bit annoyed when people just throw out the at times brilliant research done on the matter by many many hard working and smart individuals. The auditory system is at times extremly impressive, and extremly interesting, I would advice most people to read som litterature about it, and maybe marvel about the incredible capabilitis we actually have, instead of ones we don't have.

AtW

I figured you'd come to the wrong conclusion about about my stance. Something about bias and all that...

I absolutely care about measurements. How could I not? I take pause when some say to pay attention to them, but excuse the practice of actively looking for less-than-flat results. Is that not counter-productive? Could we not EQ from a flat response to something more suitable? Of course, and in most cases we should, since not every room will respond the same way. To start with something less than flat is making one's work harder, and will doubtlessly introduce interesting artifacts. This changes though when one is simply pulling a speaker out of the box with little to no EQ.

It's also problematic when we assume that the measurements will, if it fits one person's requirements, will be a universal template to all.

Sometimes people forget this is an A/V industry. Implied in that is the need to market to a broad set of individuals. Flat is not the sole market. In that case, measurements aren't really all that relevant, since the people that care little about room treatments are also less likely to pay attention to room plots. All they know is their "receiver calibrates the room with a button push".

So am I playing both sides of the fence? Absolutely. It's called being realistic vs. dogmatic.

The market for a treated, professionally calibrated system is only part. For what I would estimate is the remaining 90%, what sounds good is what matters. Even ID speaker companies know that "listening through white papers" is not the whole story, hence their liberal return policies.

This is where you are assuming more then what this thread is about.

Again, your post would suggest we are trying to force accuracy measurements upon everyone and that is not true. Actually this thread is not even about accuracy, its simply about measuring sound and how all measurements can relate back to how speakers sound. Its more about the connection between measurements and speaker performance. Even if measurements show that a speaker is inaccurate they still are important to the characteristics of a speaker.

Some people posted that they love to know that there speakers are accuracte, I also enjoying knowing that my speakers are pretty damn good measurements/sound,etc. We do go off on a tangent and I guess we started to use "accuracy" in all the discussion but that still not the intent of the thread.

Other then that, your last post made points that we all have posted and acknowledgements have been made.

btw, Im happy that you do find measurements useful!

Frankly, the more i read about the auditory system (i try to use that word, since the brain is a big part of how we hear), the more impressed I am with the incredible performance it can have in manu situations. That beeing said, for some thing the auditory system is not very good (or is easily fooled, or whatever you want to call it), and I certainly have little faith in all the strange claims about what humans can hear. And frankly i get a little bit annoyed when people just throw out the at times brilliant research done on the matter by many many hard working and smart individuals. The auditory system is at times extremly impressive, and extremly interesting, I would advice most people to read som litterature about it, and maybe marvel about the incredible capabilitis we actually have, instead of ones we don't have.

AtW

Very impressive indeed but they are inaccurate when used as measuring tools. Well maybe inaccurate is not the word but our ears can not translate or accurately identify the problems inherent in most speakers and rooms. For that we need to use measuring tools.

Maybe I (a) misremembered or (b) remembered something from 10 years ago that has been disproven, but I thought I had read fairly strongly agreed-upon research indicating that the supersonic? frequencies could modulate the audible sound in ways that are audible. Ah, well . . .

At the risk of returning to the subject of the original post:

Speakers and amplifiers are measured for frequency response using a series of single tones.


Not for the last 20-30 years, by anybody who knows what they are doing. Most measurements today are made using test signals that includes the following:

(1) Any recording with a sufficient range of frequencies in the music on it.
(2) Multiple (dozens!) concurrent tones that may have a musical sound to them
(3) Swept tone(s).
(4) Some sort of pseudo random signal that sounds like a giant whoosh!

That all said, these methods very often give the identical same results as the single tones that you claim aren't any good.



Amps are measured for distortion using a single, static tone. Even IM distorition is measured only with a single pair of closely spaced tones (typically 19K+20K).


Not necessarily, for the last 20-30 years. Most measurements today are made using test signals that includes the following:

(1) Multiple (dozens!) concurrent tones that may have a musical sound to them
(2) Swept tone(s).
(3) Some sort of pseudo random signal that sounds like a giant whoosh!
(4) single, twin, triple or whatever kind of tones that are desired.

That all said, these methods very often give the identical same results as the single tones that you claim aren't any good.


None of this touches other issues like phase shift, which, as I understand it, can be audible.


Wrong again. Many of the kinds of test signals I listed above can be used to measure phase shift, as well.

And you're right - phase shift may or may not be audible. It generally has to be pretty extreme to be audible.


I've never heard a demonstration that shows me what a signal with certain frequencies phase-shifted sounds like, so I don't know.


I have on many occasions, and often phase shift makes no audible difference at all.



I assume that phasing issues are part of what make recorded sound seem unnatural (i.e. you can tell it's a recording, not a guy standing in front of you talking).


Bad assumption. I do a ton of live recording (over 200 groups recorded just this year so far) and I could write a book about why recording as we do it today can't possibly sound perfectly natural. Many people blame the electronics but they generally are the most blameless of all.



Nor have I addressed energy storage in speaker cabinets,


One of those thiings that some people pontificate on to scare young children and the uniformed. ;-)



etc, which you can see on speaker test waterfall plots, and which may not be revealed by a speaker's frequency response,


It's generally there, you just have to know how to look.


But distortion in speakers is roundly ignored,


Maybe by measurementalists who pander to consumers. Not so for people who are into audio professionaly.



although I have always seen anecdotal asides that indicate it probably is significantly higher than electronics distortion.


Probably? Are you trying for an award for understatement? ;-)

Almost always, please!



How accurately a speaker responds to a series of single-note sine waves may not tell you whether, when given a much more complex input, its distortion signature collects harmonics in the lower treble/high midrange presence region.


You're obviously over your head.



That could make a "flat" speaker sound bright.


In the sense that even the cheapest amplifer is flat, there are no flat speakers. Period.


I wonder whether it would actually be possible to run a test using a music signal, or a soundtrack, and compare the waveform going in with the waveform produced by the device (amp or speaker).


Been there done that many decades ago. It's not the revealatory experience that you may be dreaming of.



You would think that with adequate computing power you could correct for microphone or other testing equipment anomalies as well as for the relative levels, then just compare the two, and see how close they are.


Been there done that many decades ago. Again, it's not the revealatory experience that you may be dreaming of.




Instead we have tests that are stand-ins for the real thing and have to assume that they give us enough information to at least begin with.


At this point, no need to assume. As I said before, lots of common kinds of equipment can now be performed with musical recordings as the stimulus. After you go through all the work, you find few if any new blessings.



Maybe it's been done and I just don't know about it. It's certainly not my area of expertise.


Hold that thought!

[img]
Most people here do not care to have "scientific" data thrown at them;


Particularly when many people start suspecting that the scientific data is not exactly making them look good.

Is that the fault of the people who are in error, or the data, or the people presenting the data?


The only ones that do are the Google scientists here that engage in such talk
for mutual masturbation purposes.

So you seriously think that there are no really solid technical types around here?

Umm, *don't* hold that thought! ;-) I'm just a little frog, but I do know that there are big frogs around here, and who some of them are.

While I tend to agree that IM is probably related to THD, the reason people started doing IM as I understand it is because early in the solid state revolution, people were making amps that measured beautifully on THD and had high power bet did not sound good.


No, IM distortion measurements were done in the 1950's for hollow-state amplifiers, too. The typical measurement from them was pretty simple due to hardware, but it was there, and reported. It was very important to determine the quality of output transformers, for instance.



I don't know what an MLS input looks like, so I'll defer. My point was simply that the more harmonics you get going, the more distortion may be audible (and , I assume - - yes I know it's an assumption) measurable.


Nope, with very broadband signals you'll find it impossible to measure distortion very well at all.


Easy to hear if you plug a guitar into a tub amp that's cranked to distort a bit. One note, especially a relatively high in pitch note, may not sound very "crunchy" lower notes may sound pretty crunchy along, but play a classic power chord - - easy harmonics, bypically 1-5-1 are the notes - - and the level of audible distortion really umps up.


That's a musical decision. Guitar amps are part of the artistic side, not the reproduction side.



While I understand the concept that all sounds can be represented by a series of sine waves, I've never fully wrapped my head around whether that's what the "natural" sounds are, or just a way to represent them reasonably accurately.


It's a complete representation of any real signal, well, barring some very violent physics that will not be good to be in the same solar system as...

As to reported test results, they are, to paraphrase Douglas Adams, "Mostly Harmless".

I would really encourage you to further study on this matter. It is such a fundamental concept that it is hard to evaluate anything in sound measurement without this understanding.

Regards,
Terry

A very good book on the subject is "Fourier Analysis" by Norman Morrison, Wiley Interscience.

Penngray,
Perhaps it is time for you to give us a straw man on what you think should be measured, and how we might interpret those measurements? Please be as specific as possible.

For example, what do you measure on your speakers? How does it reflect on what you hear? I assume you measure in your room. Do you think your measurements would transcribe to other rooms?

I love the concept of measuring and being scientific. I'm not convinced that measurements alone can help me choose the speaker best suited to my preferences.
It is a lofty goal. As near as I can tell we are just touching the surface. Still a useful thing to pursue. I love having dreams!

David

edit: If other people have suggestions on the best way to proceed I'd love to hear them.

Penngray,
Perhaps it is time for you to give us a straw man on what you think should be measured, and how we might interpret those measurements? Please be as specific as possible.

For example, what do you measure on your speakers? How does it reflect on what you hear? I assume you measure in your room. Do you think your measurements would transcribe to other rooms?

I love the concept of measuring and being scientific. I'm not convinced that measurements alone can help me choose the speaker best suited to my preferences.
It is a lofty goal. As near as I can tell we are just touching the surface. Still a useful thing to pursue. I love having dreams!

David

edit: If other people have suggestions on the best way to proceed I'd love to hear them.


Ugh.....Its like I have been asked to hand a paper for review :eek: ;)

Well, first I do not know everything that can be measured and I do have have all available mesurements.....hence the thread :D

Also you have to realize that Im in the DIY world so I would not buy a speaker instead I love to build them so far using expert advice/ proven designs, etc. (Im now starting to build my own crossovers :eek:)

I guess I already accept that if a speaker/drivers measures well then Im going to absolutely love them if the cabinet/baffles are build properly. I look for the flatest response possible, impedance curve, best distortion measurements and sometimes off axis response will be important.

If Im search for individual drivers, FR, Distortion, Induction, simulation of crossovers/impedance/phase and so on and so on are going to matter. Again, I am not the expert but what I have noticed is that speaker building is very, very much about the numbers and the science. You get those right and you have a high probability of a great sound speaker.

This is a different appoarch then everyone out there going into stores and just listening but I believe my appoarch is better because I do know the speakers Im interested in will have very good measurements and as I have said too many times I refuse to trust my ears because too much bias will distort my opinion.

After all the above measurements/data and things are checked of course we still have to listen and I have yet to find/read or hear about a quality build/quality crossover/quality driver choice sounded bad.

None of this has to do with Warm/Bright/detail sound search either because that is not what I believe the focus should be...you "dial in" those specific needs in house.Meaning, I believe well design speakers have the ability to transform to the needs of the owner. Well designed speakers can be bright, can be warm, can be whatever floats your boat on that day if you have the equipment in house to "dial in" those accurate/well built speakers.

My current solution is that I decided to go with active design. The DIY forum and all the experts there help me figure this path out. Active allows you to worry less about the issues of crossovers and lets you tweak your speakers as desired. The only difficultly then is picking matching drivers. There are lots of drivers to choose from and we can either buy many and listen or trust what others have already matched together. Several individuals helped me with that (Thy, John, Mark, Jay....). I still looked at all the measurements of each driver to make sure I had a sense of what they could do. One big downside is that I need 9 amp channels for 3 main speakers :( I even built different baffles to experience the differences....MT vertical and horizontal, I wanted understand what changes.

In the end I like the flexibility of my speakers...they are whatever I want them to be...warm,bright, detailed. Change is easy with a couple buttons/dials.

I really think speaker selection is extremely habit based. Choosing speakers was all about listening for 50+ years. Now with the internet and the amount of data/information/tools avialable we have a new paradigm. I think DIYers see this more then others, we see how easy it is to understand speakers from the inside out. We also see how companies do or do not build good speakers and how that correlates to their sales (or how it doesn't ;) )

I guess I believe that speakers do not have to be subjective at all. Successful speakers purchases can be done using lots of objective analysis instead of the age old idea of just listening. Not everyone needs to stimulate their senses to buy a product, if there is enough data and buyer protection there is actually no need for majority.

Well, if we're going to measure system error to a complex signal, the very first thing we have to do is figure out the linear-systems part, i.e. complex frequency response. We have to do that, because we want to both publish that part AND process our reference signal in exactly that way before we figure out the error spectrum.

Then we figure out the error spectrum. That, a copy of Flecher, a copy of Zwicker, a copy of Brian Moore's book, or a copy maybe of Yost's book, and you can figure out more from there. :)

But error spectra compared to the original signal is very, very much a key bit of information.

Yes, if all you want to know is pressure. There is also particle velocity, which is of course a vector. It is easily measured via a directional velocity transducer, such as a soundfield-type microphone.

- Terry

Then why are we still stuck with such limited vector information in our recordings. 2!! at most 7! cough cough, DTS, cough cough,

Then why are we still stuck with such limited vector information in our recordings. 2!! at most 7! cough cough, DTS, cough cough,
Practicality?

Then why are we still stuck with such limited vector information in our recordings. 2!! at most 7! cough cough, DTS, cough cough,

Well, given the number of times I've pointed out that the soundfield at one point has 4 components, I'm not sure why you're coughing in my face. What's your point, mate?

Now, let's ask you a question:

How much of the soundfield that we observe in a space is actually perceptable?

And another question:

How many channels would you need to capture the soundfield with in a 1 meter sphere around your head in order to obey the (spatial) samping theorem for a frequency range of DC to 20kHz?

This might help you a bit in your understanding.

If you want to record the pressure plus the three velocity components at any point in the sound field, you need to use something like this:

http://www.agmdigital.com/page2/files/page2_blog_entry4_1.jpg

Such mics are standard gear for ambisonic recording, and also for acousticians who need to compute quantities which are directional, such as Lateral Energy Fraction (a crude measure of spaciousness).

- Terry

I've mentioned in other threads that I believe fidelity rests in the hands of video games. In Windows XP with no hardware acceleration I believe it can mix 20 channels in real time. (I used to play alot of Battlefield 1942 back then. This was back with 2002 computer hardware.)

In 2000ish there was a game half life which utilized Aureal A3D technology. There was one particular level where a flying helicopter wih a gun kept killing me. To look up in virtual space and navigate around objects on the ground without looking at the ground is very difficult. So I simply listened to where the helicopter was and ran around objects for cover. I didn't have any visual queues as to where the chopper was. The task was so frustrating without the sound information and so amazingly simple with. I was either using some Koss headphones or a Sony CD/radio/tape player with the sony speakers. I think that computer was only capable of 8 channels.


Number channels != number of speakers.
One day we will be mixing in realtime. It can accomodate 2.0, 5.1, 10.1, 30.1.
Personally I do not insist on recording vector information because I divulge artistic content and as such I am more interested in what the creator wants.

Then there is no subjectivist retort and the room is also accounted for by equipment smarter than the consumers.

I suggested DTS because here we have a guy with some influencial power and technical prowess.
More equipment to buy, more fidelity [I]and[I] I don't have to upgrade. I can keep my old speakers. Who doesn't win?

If you want to record the pressure plus the three velocity components at any point in the sound field, you need to use something like this:

http://www.agmdigital.com/page2/files/page2_blog_entry4_1.jpg

Such mics are standard gear for ambisonic recording, and also for acousticians who need to compute quantities which are directional, such as Lateral Energy Fraction (a crude measure of spaciousness).

- Terry

Well, they can also tell you the total energy stored in a soundfield with many fewer measurement points :) too.

How much of the soundfield that we observe in a space is actually perceptable?

I have no idea. Just a guess if I turn my head 2 degrees left and right I think I could detect a change in direction. Up and down maybe 10 degrees?



How many channels would you need to capture the soundfield with in a 1 meter sphere around your head in order to obey the (spatial) sampling theorem for a frequency range of DC to 20kHz?

I have no freakin idea. But why do we have to capture the soundfield vector information. Can't we just fake it in a virtual space? All of these matrix based upmixers essentially try to recreate a virtual acoustic space with archaic vector information...2 vectors. Why can't we embed more vector information?

Well, if we're going to measure system error to a complex signal, the very first thing we have to do is figure out the linear-systems part, i.e. complex frequency response. We have to do that, because we want to both publish that part AND process our reference signal in exactly that way before we figure out the error spectrum.

Then we figure out the error spectrum. That, a copy of Flecher, a copy of Zwicker, a copy of Brian Moore's book, or a copy maybe of Yost's book, and you can figure out more from there. :)

But error spectra compared to the original signal is very, very much a key bit of information.

This, or similar, methods have shown some promise in being able to quantify the perceptibility of different patterns of non-linear distortion. For example: http://projekter.aau.dk/projekter/fbspretrieve/9852082/07gr1061_Thesis.pdf

My own informal experiments in this field tend to confirm their conclusions but there seems very little interest in adopting such perception-based measurements. Perhaps, to quote Earl Geddes, we stick to traditional THD and IMD "because the light is better". :o

This, or similar, methods have shown some promise in being able to quantify the perceptibility of different patterns of non-linear distortion. For example: http://projekter.aau.dk/projekter/fbspretrieve/9852082/07gr1061_Thesis.pdf

My own informal experiments in this field tend to confirm their conclusions but there seems very little interest in adopting such perception-based measurements. Perhaps, to quote Earl Geddes, we stick to traditional THD and IMD "because the light is better". :o


The conclusion of the paper is:

"From the nonlinear threshold experiments, it was concluded that nonlinear distortion thresholds are dependent on the type of applied
distortion and on the characteristics of the stimulus."

In case you don't recognize it, this is a well-known truism.

I'm happy that the paper was pleasing to the people who prepeared it, but it was time wasted for me to read it. :-(