Horns vs. direct radiators, and their sonic differences - Page 5 - AVS Forum | Home Theater Discussions And Reviews
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post #121 of 188 Old 05-22-2019, 11:58 AM
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Originally Posted by noah katz View Post
Is that for EQ'd or raw response?

If the latter, I believe distortion is being overestimated because peaks are at resonances that would be EQ'd down.

But maybe not, as I don't see the 54 Hz spike.
The peak there I highlighted is around 62hz, and there is no corresponding peak in frequency response.

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post #122 of 188 Old 05-22-2019, 12:49 PM
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Quote:
Originally Posted by notnyt View Post
The peak there I highlighted is around 62hz, and there is no corresponding peak in frequency response.

OK.

Eq'd or not?

Noah
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post #123 of 188 Old 05-22-2019, 12:51 PM
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Originally Posted by noah katz View Post
OK.

Eq'd or not?

What was the input signal?

Not eq'd, that was from data-bass. There is no peak at that frequency. The graph shows a full frequency range.
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post #124 of 188 Old 05-22-2019, 02:46 PM - Thread Starter
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Originally Posted by notnyt View Post
You should always have a highpass.
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Originally Posted by SteveCallas View Post
I’ve had the LLTs since 2005 with no highpass and ive never bottomed them with low frequency bass. In fact, in 14 years, ive only managed to bottom one of the subs twice, and it was due to a faulty rca to 1/4 jack.
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Originally Posted by MKtheater View Post
Speaking of which, my 4 LLT subs never bottomed and my two DTS-10s complained only a couple times. I have a smaller room though, well actually, I don’t anymore.
Apart from preventing sub drivers from bottoming with a highpass, is there an incentive for using a HP in regards to minimizing distortion? To explain: even though one would easily be within the safety zone of a given driver and its xmech (say, in a tapped horn where the driver is unloaded below the tuning frequency), reaching SPL's with at least a remaining +15dB's headroom, would there be a potential sonic advantage using a highpass here compared to omitting the HP?

With that in mind it seems there's some consensus, at least with tapped horns, to use a HP with at least 24dB/octave slope for the HP to have proper and significant effect protecting the driver. However, can the slope steepness be exaggerated with a, say, 48dB/octave slope (Butterworth)? Some speak of steep HP slopes and how they can possibly lead to "ringing"/overhang in bass. In my own setup I've experimented with a 20Hz HP 24dB/octave Butterworth over the MicroWreckers, but it roles off the response just a bit earlier compared to using a steeper slope - that is, above 20Hz. Therefore I'm now trying out a 48dB/octave BW slope, and while I haven't measured the response it clearly feels as if the bass now extends a bit more fully and freely down to ~20Hz. Subjectively I don't notice any downsides with the steeper HP (using a Xilica XP-3060)..

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post #125 of 188 Old 05-22-2019, 03:07 PM
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Quote:
Originally Posted by rezag View Post
Apart from preventing sub drivers from bottoming with a highpass, is there an incentive for using a HP in regards to minimizing distortion? To explain: even though one would easily be within the safety zone of a given driver and its xmech (say, in a tapped horn where the driver is unloaded below the tuning frequency), reaching SPL's with at least a remaining +15dB's headroom, would there be a potential sonic advantage using a highpass here compared to omitting the HP?

With that in mind it seems there's some consensus, at least with tapped horns, to use a HP with at least 24dB/octave slope for the HP to have proper and significant effect protecting the driver. However, can the slope steepness be exaggerated with a, say, 48dB/octave slope (Butterworth)? Some speak of steep HP slopes and how they can possibly lead to "ringing"/overhang in bass. In my own setup I've experimented with a 20Hz HP 24dB/octave Butterworth over the MicroWreckers, but it roles off the response just a bit earlier compared to using a steeper slope - that is, above 20Hz. Therefore I'm now trying out a 48dB/octave BW slope, and while I haven't measured the response it clearly feels as if the bass now extends a bit more fully and freely down to ~20Hz. Subjectively I don't notice any downsides with the steeper HP (using a Xilica XP-3060)..

Yes, if you highpass and remove the content where the woofer unloads you will have cleaner output overall when such signal is present. Also, it will prevent bottoming out your drivers. Because someone on the forum has run without a highpass for eleventy years without a problem does not mean it's good practice or should be encouraged.

You're not going to get ringing from any proper highpass filter. I generally use a 3rd or 4th order butterworth depending on the enclosure/woofer somewhere around 1/4 octave below tune depending on how everything models.
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post #126 of 188 Old 05-22-2019, 03:08 PM
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Correct, a really steep filter will lead to some ringing, but at a low enough frequency it probably doesnt matter.
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post #127 of 188 Old 05-22-2019, 07:48 PM
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Originally Posted by rezag View Post
"Horns" as a term has been around for so long that it precedes marketing considerations
Nonsense. "Marketing considerations" precede any product.

The fact of the matter is that these boxes are degenerate bandpass alignments, not "horns." They can work well, or not. That's a separate issue.

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From my chair going dual subs would be a minimum requirement so to make way for a symmetrically placed setup (in relation to the mains)
There's no requirement for "symmetry." Indeed, decorrelating subwoofer placement will randomize room mode excitation and likely lead to better sound with less required processing in many rooms.

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Sound quality of subwoofers is kind of a silly topic in the sense that very, very few people here or elsewhere have ever truly tested it properly.
Mostly right. Basically if a subwoofer system looks acceptable in the room, will play as low as one wants, get as loud as one wants, and has flattish and smooth response at least an octave (better 2) above the nominal lowpass...then one is well advised to shift one's focus elsewhere!

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Originally Posted by SteveCallas View Post
Subwoofers are not “musical”, they have no “airiness”, and you won’t hear more “detail” from one vs another.
Mostly right. There are some extreme cases of bass drivers that just suck, though. I'll give you two examples from my past: Stryke (TC Sounds) HE15 and Ascendant Ava18. The problem with these two drivers is out of control inductance. Both the absolute level and the variation over stroke. I replaced my Ava18 with an Exodus Audio Maelstrom-X, which was similar (18" with long stroke dual gap motor) but had one major improvement: meaningful induction management in the motor. The difference between the two, even played alone with a low crossover, was clear.

Admittedly, measurement tech and EQ tech were both less advanced back then. The only affordable mainstream room correction was Audyssey, which people with good taste and quality speakers did not use due to the non-defeatable crappy speaker compensation notch, neutered room gain, and twitchy HF correction tendencies. Subwoofer EQ was global, from a device such as a Velodyne SMS-1. (More adventurous people did use Behringer EQs.) Perhaps with modern measurement technology and DSP one could even get music out of pigs such as the HE15 or Ava18.

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Integration with the mains is not a feature of the subwoofer sound quality, its a room, phase, and distance setting function.
It's also a function of the subwoofer's response smoothness above its nominal highpass. Also, integration is generally better IME with mains full range and multisubs folded in, assuming the mains are sufficiently capable closed boxes. (If they're not, they should be upgraded before futzing with subwoofers.)

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Originally Posted by Chris Popovich View Post
Back to OP; I still really like a ton of sealed boxes. Lots of cone area, smallish, easy to place, easy to eq, very low group delay, very low distortion (assuming you really have enough of them) no port or horn resonances, it's a bummer you lose so much on output but that's my fav.
The thing about output is: if you have enough, you have enough.

Also, there are two ways to increase a system's ULF efficiency: more box, and additional motors. People talk about how efficient these giant subs are. But take that same cabinet volume, close the box, and add more motors you're going to get equal or better results in the ULF. Above that...room modes are tricky, so who knows.

I too prefer multiple smallish closed boxes. Which, of course, do not need to be the same size or use the same drivers. Anyone who's ever competently calibrated multiple subwoofers knows that some may be set ≤12dB quieter than others. (That assumes use of modern calibration techniques, rather than dumb and primitive hacks such as "level matching" or "gain matching" that do nothing to optimize room mode excitation.) Given that, if you're DIYing the subs, you can tailor the capability of each one to its actual role in your system.

If one doesn't care about extreme ULF, multiple smallish passive radiator subs work too. Frankly if ~20Hz is sufficient, it's still hard to beat the old Peerless XLS12+PR "application note" sub design as a size/SQ/SPL/cost compromise.

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Originally Posted by boostick4 View Post
To dump my 2 cents in the pool, I have attached a measurement I did a while ago:

Driver: Dayton RSS390HF (same driver used in both enclosures)
Amp: same channel of EP4000 @ the same power
EQ: None
Environment: 18” away from living room corner
Mic: Dayton OMNI mic
Sealed enclosure: 7.5 ft^3
FLH enclosure: 24” wide THT @ 18 ft^3

This goes back to what I wrote above: shrink the 4th order bandpass cabinet to 15 ft^3 and add another RSS390HF in parallel, and you'll see similar results as your 18 ft^3 bandpass box, except the ULF will be stronger with two motors instead of one. In real terms multiple motors in smaller box may even be cheaper: you have to account the value of the real estate occupied by the subwoofers.

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Originally Posted by SteveCallas View Post
Accuracy still favors the LLT alignment. It is what it is.
Port resonances can be very deleterious. An EBS alignment ("LLT" is just an attempt by someone to get forum points for renaming a long-established concept) is fine, but you have to take extreme care to avoid such resonances. IMO, pipes are for HVAC and plumbing, not audio.
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post #128 of 188 Old 05-22-2019, 08:12 PM
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Port resonances above 190hz, a design characteristic of LLT, which is greater than a full octave above crossover to the subwoofer, is of no concern, and does not require extreme care to achieve.

This forum still gets the occassional red herring - first group delay below 15hz and now port resonances above 190hz. Some things never change.

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post #129 of 188 Old 05-22-2019, 08:24 PM
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Originally Posted by SteveCallas View Post
Port resonances above 190hz, a design characteristic of LLT, which is greater than a full octave above crossover to the subwoofer, is of no concern, and does not require extreme care to achieve.
Nonsense. When you have high displacement transducers and want to keep port compression to a minimum, it is not trivial to keep the port resonance above 190hz.

I have a port resonance around 110hz. It is not audible, though it is visible in the time domain if you know what to look for. Still, you wouldn't be able to tell it apart from some other room artifact even in my heavily treated and large room. That said, port resonances should be kept as far out of the passband of the sub as possible.
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post #130 of 188 Old 05-22-2019, 08:46 PM
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Originally Posted by SteveCallas View Post
Port resonances above 190hz, a design characteristic of LLT, which is greater than a full octave above crossover to the subwoofer, is of no concern, and does not require extreme care to achieve.

This forum still gets the occassional red herring - first group delay below 15hz and now port resonances above 190hz. Some things never change.
"Play the sub by itself" was your standard.

I presume you can hear a pipe whistle at ~190Hz if you listen to the sub by itself. Also, 190Hz is often less than an octave above the subwoofer lowpass in a thoughtfully-designed system. IME the sweet spot tends to be closer 120Hz global lowpass for a generic distributed multisub system, up to 150-200Hz if one employs sophisticated DSP matrix routing and use of flanking subs. (That's global; individual subs may have lower individual low passes based on location, proximity to things that might rattle, etc.)

Lyngdorf, as I understand it, takes the flanking ("boundary") subs all the way up to 400Hz as part of their RoomPerfect setup.

That said, given obscenely large cabinets, yes an infrasonic-tuned EBS alignment with minimally invasive port whistling is possible. So if one "needs" that kind of output...whatever. Those of us who don't have a deaf wish - or, I suppose, a genuinely auditorium-sized listening space - can't relate.

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post #131 of 188 Old 05-22-2019, 08:52 PM
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Originally Posted by DS-21 View Post
An EBS alignment ("LLT" is just an attempt by someone to get forum points for renaming a long-established concept) ...
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Originally Posted by SteveCallas View Post
Port resonances above 190hz, a design characteristic of LLT...

I agree with DS-21, and citing port resonance freq as a design characteristic is really pushing it, and a first AFAIK.

I have no problem with the LLT moniker, since that perfectly describes this variation on EBS.

Noah

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post #132 of 188 Old 05-22-2019, 09:16 PM
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Originally Posted by DS-21 View Post
"Play the sub by itself" was your standard.

I presume you can hear a pipe whistle at ~190Hz if you listen to the sub by itself. Also, 190Hz is often less than an octave above the subwoofer lowpass in a thoughtfully-designed system. IME the sweet spot tends to be closer 120Hz global lowpass for a generic distributed multisub system, up to 150-200Hz if one employs sophisticated DSP matrix routing and use of flanking subs. (That's global; individual subs may have lower individual low passes based on location, proximity to things that might rattle, etc.)

Lyngdorf, as I understand it, takes the flanking ("boundary") subs all the way up to 400Hz as part of their RoomPerfect setup.

That said, given obscenely large cabinets, yes an infrasonic-tuned EBS alignment with minimally invasive port whistling is possible. So if one "needs" that kind of output...whatever. Those of us who don't have a deaf wish - or, I suppose, a genuinely auditorium-sized listening space - can't relate.
Lol, now port resonances whistle?

This is great.
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post #133 of 188 Old 05-22-2019, 09:25 PM
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Even if you play the sub by itself, you wont hear a resonance above 190hz. Here in the real world, people cross to subwoofers at 80hz.

@notnyt - i dont know about your designs, but a large enclosure allows for large diameter ports with low tunes that dont need to be extraordinarily long.
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post #134 of 188 Old 05-22-2019, 09:33 PM
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Originally Posted by SteveCallas View Post
Even if you play the sub by itself, you wont hear a resonance above 190hz. Here in the real world, people cross to subwoofers at 80hz.

@notnyt - i dont know about your designs, but a large enclosure allows for large diameter ports with low tunes that dont need to be extraordinarily long.
Decrease port volume, you get compression.

Go ahead and model a pair of LMS 5400 ultras in a 27 cubic foot enclosure with 6kw power applied and let me know how low you get your port resonance.

Had I used lesser drivers and applied less power then sure, I could use a smaller port. Either way, not really relevant, as the resonance is inaudible.

As is:





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post #135 of 188 Old 05-22-2019, 10:40 PM
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Lms never modeled well for me in LLT, i wouldnt personally use it in such an application. Many other drivers better suited based on their parameters, but to each their own.
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post #136 of 188 Old 05-22-2019, 10:48 PM
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Originally Posted by SteveCallas View Post
Lms never modeled well for me in LLT, i wouldnt personally use it in such an application. Many other drivers better suited based on their parameters, but to each their own.
LMS model and perform excellent in large enclosures, not sure why you think otherwise.
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post #137 of 188 Old 05-23-2019, 12:26 PM
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Originally Posted by notnyt View Post
Lol, now port resonances whistle?



This is great.

Forum hyperbole, admittedly.

True whistling from subs tends to come from air leaks arising from build quality or parts issues, such as using leaky binding post kludges instead of proper Speakons.

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Originally Posted by SteveCallas View Post
Even if you play the sub by itself, you wont hear a resonance above 190hz.
Thanks for confirming you have not actually done the comparison.

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Originally Posted by SteveCallas View Post
Here in the real world, people cross to subwoofers at 80hz..

Yes, there are people who are shackled to rules of thumb and are afraid to experiment. That is their burden.
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post #138 of 188 Old 05-23-2019, 12:48 PM
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Originally Posted by notnyt View Post
This is distortion by frequency of the dts-10. You can see it reaches these levels of distortion well before it's max output limitations.

There are other horns that can do this cleaner, but just using this as an example since it's been talked about quite a bit.

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Is that for EQ'd or raw response?

If the latter, I believe distortion is being overestimated because peaks are at resonances that would be EQ'd down.

But maybe not, as I don't see the 54 Hz spike.
That is the raw voltage response. Remember we are looking at distortion harmonics. The response peak at 54Hz does show up in the THD graphs. We see the big jump in THD at 27Hz where the second harmonic falls at 54Hz and there is a small jump at 18Hz where the 3rd harmonic would fall at 54Hz.


EQ won't cure that type of distortion. If you cut at 54Hz you aren't affecting 18Hz or 27Hz, etc where their distortion harmonics being generated are acoustically boosted by the response. EQ can help with ringing and a rough response shape, but not this.
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post #139 of 188 Old 05-23-2019, 02:37 PM - Thread Starter
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There's no requirement for "symmetry." Indeed, decorrelating subwoofer placement will randomize room mode excitation and likely lead to better sound with less required processing in many rooms.
Decorrelating the placement of subs necessitates a lowpass below ~60Hz so not destabilize the stereo image, I find (as such I've found multiple smaller sub setups to be capable, but I still prefer setups with 2 larger, symmetrically placed and higher crossed subs, although they may take more effort to achieve a smooth response/coverage). Symmetry becomes relevant with a crossover to the mains from ~80Hz on up, IME, and also makes phase adjustment much easier.

Quote:
It's also a function of the subwoofer's response smoothness above its nominal highpass. Also, integration is generally better IME with mains full range and multisubs folded in, assuming the mains are sufficiently capable closed boxes. (If they're not, they should be upgraded before futzing with subwoofers.)
I prefer high-passing the mains no lower than 80Hz with a quality digital crossover, which relieves both the mains and their amp with better dynamic range/headroom to boot. My all-horn mains roll off below 60-65Hz, and while I've had them running full-range I definitely find it to be an advantage high-passing them no lower than 80Hz. It simply lends more ease and better overall coherence to the presentation. This goes for other setups I've heard as well, but I wouldn't want to generalize..
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Thanks for explaining; I knew there was an important concept I had forgotten about (your 2nd paragraph).

Also tricky is that the distortion plot looks like freq response, but it's not - the 2nd harmonic shows as a peak at 27 Hz, not at 54 Hz.


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That is the raw voltage response. Remember we are looking at distortion harmonics. The response peak at 54Hz does show up in the THD graphs. We see the big jump in THD at 27Hz where the second harmonic falls at 54Hz and there is a small jump at 18Hz where the 3rd harmonic would fall at 54Hz.


EQ won't cure that type of distortion. If you cut at 54Hz you aren't affecting 18Hz or 27Hz, etc where their distortion harmonics being generated are acoustically boosted by the response. EQ can help with ringing and a rough response shape, but not this.

Noah
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post #141 of 188 Old 05-23-2019, 04:39 PM
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Decorrelating the placement of subs necessitates a lowpass below ~60Hz so not destabilize the stereo image, I find
Not really possible, assuming halfway competent calibration.

You want to destabilize a stereo image? Put a tweeter horn horizontally next to a midrange horn, with wide spacing between them and clearly different radiation patterns to boot!



(Beautiful woodwork, though.)

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My all-horn mains roll off below 60-65Hz
That looks like two horns on top of an oddly-tuned bandpass cabinet...
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post #142 of 188 Old 05-23-2019, 06:58 PM
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Originally Posted by noah katz View Post
Thanks for explaining; I knew there was an important concept I had forgotten about (your 2nd paragraph).

Also tricky is that the distortion plot looks like freq response, but it's not - the 2nd harmonic shows as a peak at 27 Hz, not at 54 Hz.
I have some measurements of a th50 take-off that are good for evaluation purposes...at least in regards to a th. they mimic other measurements ive taken of the same enclosure style, in that 2nd harmonic is constant....comprises most of thd. at the peaks of the box, 3rd harmonic dips, and in the valley where things seem good, 3rd harmonic is at its highest. this is with rew and im not josh....but ive seen a few things in my day. need to swap the NIC on that box to share images, soon as I do I can upload here.
and for any interested, I also eq'd that th flat(ish) and did power compression sweeps with that and a 20"x20"x20" sealed enclosure eq'd flat(ish) (albeit a different 15" driver) if anyone wants it for science.

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Not really possible, assuming halfway competent calibration.

You want to destabilize a stereo image? Put a tweeter horn horizontally next to a midrange horn, with wide spacing between them and clearly different radiation patterns to boot!



(Beautiful woodwork, though.)



That looks like two horns on top of an oddly-tuned bandpass cabinet...
looks like a home-brew la scala without a ported mod.... woodwork is gorgeous but its not the 70s anymore. fun part of standing on the shoulders of giants, they eventually die and you stand on the ground again.

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post #143 of 188 Old 05-24-2019, 02:55 AM - Thread Starter
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You want to destabilize a stereo image? Put a tweeter horn horizontally next to a midrange horn, with wide spacing between them and clearly different radiation patterns to boot!
You heard my speakers? Obviously not, but I gather you don't need to to form your opinion.

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That looks like two horns on top of an oddly-tuned bandpass cabinet...
It is what it is, a one-fold horn. Can't comment on the oddity part, but strictly speaking having it play up to ~500Hz is a bit too high, which is due to the fold itself and not the 15" driver inside. Compromises - they reside most everywhere. On the upside I have 105dB measured sensitivity, good coherency and dynamics.

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Originally Posted by VegaMan View Post
looks like a home-brew la scala without a ported mod....
They are Simon Mears Audio Uccello's, inspired by the Klipsch Belle. Bass horn is more or less similar, the rest is not - drivers and everything. Construction quality way better. And btw., I cherish the lack of the "ported mod."

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woodwork is gorgeous but its not the 70s anymore.
Fortunately I couldn't care less about fashion trends. I do however adore gorgeous woodwork (thanks) that actually looks, feels and smells like wood and isn't lacquered to death. Moreover I just happen to like paldao, which in a couple of years from now might draw your attention when it's trendy again.

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fun part of standing on the shoulders of giants, they eventually die and you stand on the ground again
And how do you find this applies here?
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Last edited by rezag; 05-24-2019 at 06:03 AM.
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post #144 of 188 Old 05-24-2019, 05:26 AM
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Those uccellos are very cool. Not my cup of tea but no one asked me what tea I drink. I really appreciate the workmanship and character of a design like that. To me, as an engineer, my greatest joy is in finding the space between where the numbers, measurements, and design approaches find commonality with the magic. More pragmatically said, when the engineering meets the art. How could I find fault for someone leaning a little more towards the art than my personal preference? She's got some SOUL! I love it! It's like an older Alfa Romeo, pain in the ass in many objective ways, outperformed by a new Camry in pretty much every bench mark you can think of.... yet.... a real hoot to drive. You may not know that if you're not into cars or never drove one. If I had to just have one car, maybe it wouldn't be the Alfa (for me) but to each their own, and who says you just have to have one approach?

I have had (and restored/modded) some old Klipsch, powered with vintage gear, I never even measured them, don't care to, that's not what I like 'em for. I bet by the book they're wrong on most levels. Still make me smile and tap my foot. I like the main system better but different horses for different courses.

Not to be pedantic, but as far as the standing on shoulders of giants, I always though that meant our current knowledge was built off of that which was formerly established. Which we do. That knowledge never goes away, just gets implemented in (hopefully) better ways.

It's many of your guys Friday morning, but I've been working late nights, so this is my Friday evening and I'm ready for a long weekend. I do believe I'm going to have some scotch and listen to a little music before I catch some z's.

You sirs stay positive and remember to enjoy the music.

Chris
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post #145 of 188 Old 05-24-2019, 10:18 AM
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Originally Posted by rezag View Post
You heard my speakers? Obviously not, but I gather you don't need to to form your opinion.
You really don't need to hear them to identify design flaws such as the one he pointed out.
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post #146 of 188 Old 05-25-2019, 05:10 AM - Thread Starter
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Quote:
Originally Posted by Chris Popovich View Post
Those uccellos are very cool. Not my cup of tea but no one asked me what tea I drink. I really appreciate the workmanship and character of a design like that. To me, as an engineer, my greatest joy is in finding the space between where the numbers, measurements, and design approaches find commonality with the magic. More pragmatically said, when the engineering meets the art. How could I find fault for someone leaning a little more towards the art than my personal preference? She's got some SOUL! I love it! It's like an older Alfa Romeo, pain in the ass in many objective ways, outperformed by a new Camry in pretty much every bench mark you can think of.... yet.... a real hoot to drive. You may not know that if you're not into cars or never drove one. If I had to just have one car, maybe it wouldn't be the Alfa (for me) but to each their own, and who says you just have to have one approach?
Thanks for your remarks on the Uccello's and the "engineering meets the art"-aspect. Well put indeed.

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I have had (and restored/modded) some old Klipsch, powered with vintage gear, I never even measured them, don't care to, that's not what I like 'em for. I bet by the book they're wrong on most levels. Still make me smile and tap my foot. I like the main system better but different horses for different courses.
What's your main system?

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Not to be pedantic, but as far as the standing on shoulders of giants, I always though that meant our current knowledge was built off of that which was formerly established. Which we do. That knowledge never goes away, just gets implemented in (hopefully) better ways.
Thanks, I understood the meaning, just didn't get why it needed mention in the specific context above.

Quote:
It's many of your guys Friday morning, but I've been working late nights, so this is my Friday evening and I'm ready for a long weekend. I do believe I'm going to have some scotch and listen to a little music before I catch some z's.

You sirs stay positive and remember to enjoy the music.
Enjoy your weekend - I'm sure it's well-deserved

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Originally Posted by notnyt View Post
You really don't need to hear them to identify design flaws such as the one he pointed out.
But listening to them mayn't be sonically reflective of the design flaw that's mentioned - that's my point. My contention is "listening to the measurements" as that which impacts listening to the actual speakers, not the other way round.

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post #147 of 188 Old 05-25-2019, 09:31 AM
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Quote:
Originally Posted by rezag View Post
My contention is "listening to the measurements" as that which impacts listening to the actual speakers, not the other way round.
I don't buy the "magic special snowflake" theory of loudspeakers.

We know the foundations of good sound: flattish and smooth axial response, smooth horizontal polars (a midrange mushroom cloud is a common and audible issue), extended bandwidth, sufficient volume displacement and amplifier power to play at the desired levels, precise channel matching, etc. Ultimately it doesn't matter whether the loudspeakers use direct radiators, horns, bending petals, panels, pulsating ions, whatever.

Other potentially audible design flaws (such as an is lack of attention to detail in mouth termination here - there should not be a sharp discontinuity between the horn and the rest of the waveguide/baffle) could manifest immediately, more subtly in the long-term as listening fatigue, or not at all.

The main surprises are:
-Often excellent speakers don't instantly impress in an audition. There's no unique sonic hook for the ear-brain to grab on to.
-Sometimes that a badly measuring speaker doesn't sound quite as bad as one would expect from the measurements. That depends on program material, placement/room, availability of a reference to make direct comparisons, and other factors. Ears are pretty forgiving!

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Dispersion matters a lot.
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post #149 of 188 Old 05-25-2019, 11:39 AM
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Quote:
Originally Posted by DS-21 View Post
-Often excellent speakers don't instantly impress in an audition. There's no unique sonic hook for the ear-brain to grab on to.

I've never quite grasped this idea.

Assuming the recording and electronics have accurately captured the instruments, a good speaker will transparently reproduce them, and I'm always instantly impressed by the immediacy, clarity, and dynamics of live instruments.

So maybe it's just poor choice of program material.

Noah
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post #150 of 188 Old 05-25-2019, 04:21 PM
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Quote:
Originally Posted by rezag View Post
Thanks for your remarks on the Uccello's and the "engineering meets the art"-aspect. Well put indeed.

What's your main system?

Thanks, I understood the meaning, just didn't get why it needed mention in the specific context above.

Enjoy your weekend - I'm sure it's well-deserved

But listening to them mayn't be sonically reflective of the design flaw that's mentioned - that's my point. My contention is "listening to the measurements" as that which impacts listening to the actual speakers, not the other way round.
Thank you. Main system speakers are NHT M7's with a vast multitude of subwoofers in a 2.whatever channel system running DIRAC with a target curve of my own doing (similar to Harmon but a touch more aggressive) and a subharmonic synth (sometimes) adding some "kapow" down to around 15hz. Also flawed (tweeter is inboard of midrange), but idealized design characteristics aren't always the most important thing in the hierarchy of performance. I.e. their older brothers were good enough to garner Stereophile Class A categorization, which is by no means authoritative but enough to garner a solid listen. I love them, although my next pair will likely be something that I design and build myself.


Quote:
Originally Posted by DS-21 View Post
I don't buy the "magic special snowflake" theory of loudspeakers.

-Sometimes that a badly measuring speaker doesn't sound quite as bad as one would expect from the measurements. That depends on program material, placement/room, availability of a reference to make direct comparisons, and other factors. Ears are pretty forgiving!
That's pretty much the test-engineer's version of magic special snowflake theory. While I agree with you on everything you wrote, don't forget to add in room for the unknown. 5 years from now we'll answer the question a little different than we do today, but progress is definitely being made on many fronts, which is exciting stuff (especially the DSP territory... what a difference!).

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Originally Posted by SteveCallas View Post
Dispersion matters a lot.
Yep. When you normalize for freq response, distortion, and dispersion IMO they start sounding more alike than different.

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Originally Posted by noah katz View Post
I've never quite grasped this idea.

Assuming the recording and electronics have accurately captured the instruments, a good speaker will transparently reproduce them, and I'm always instantly impressed by the immediacy, clarity, and dynamics of live instruments.

So maybe it's just poor choice of program material.
Eh, a stripper will grab your attention when she walks into the room but maybe not the best choice for a wife. I think that's about all that means. Probably doesn't really apply to anyone who has spent a lot of time critically listening. Definitely a liability with the casual listener.


I'll leave you guys with a photo of the best speaker in the world to (quietly) listen to old twangy country music while on vacation in a small cabin in Northern Arizona with a cold beer in hand playing a game of scrabble with the wife. (I got it for $6 at goodwill, and then paid $12 for the batteries).

Chris
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