Dynamic Compression in conventional loudspeakers

morricab

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My speakers are 4 ohms, Bamberg S5-MTM, with SEAS Excel Millennium silk tweeter, and dual SEAS Excel 18cm mid-bass drivers. Sensitivity is 91dB (2.83V@1-Meter). From the specifications page:

Maximum linear output:
105 dB 64W HPF2 @80Hz, all frequencies, no compression
102 dB 32W no HPF, all frequencies, no compression


The onset of compression will not be the same for all 91dB speakers as driver choice and filter choices have a huge impact. For example, I used to sell Dynamikks speakers from Germany and we had a model called Athos 10, which in passive form was 91 dB (half active though was 97dB… the woofer really limited the passive sensitivity). All of the drivers were professional and designed to minimize thermal compression.
While not as dynamic as a horn speaker (the tweeter was a compression driver/horn) They sounded very alive compared to a pair of Thiel CS3.7, which were also around 91dB. The woofer had an absolutely massive voice coil and magnet and was running far below its capabilities at normal levels. The Coax driver was a 97dB design padded down to meet the woofer so it was cruising even at loud levels. The Thiel, while a very good speaker overall sounded dynamically constrained by comparison.
 

microstrip

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You are perhaps underestimating the effect on short peaks. With dynamic recordings it can be easily 20-30dB above average. I think there is a subtle more insidious effect that we are very sensitive to that ultimately robs realism. Kind of like distortion and jitter, how low of an effect is inaudible??

No I am assuming any transient in acoustic music. Again, if such compression existed it would be very easy to measure. The high-efficiency manufacturers are surely competent enough to do it and if proved it would be a fantastic marketing argument. Or do you think they can't handle measuring instruments?

Remember we are arguing about a measurable simple electrical effect - the dynamic change of value of a resistor (the coil of a speaker), not about rocket science!
 

morricab

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No I am assuming any transient in acoustic music. Again, if such compression existed it would be very easy to measure. The high-efficiency manufacturers are surely competent enough to do it and if proved it would be a fantastic marketing argument. Or do you think they can't handle measuring instruments?

Remember we are arguing about a measurable simple electrical effect - the dynamic change of value of a resistor (the coil of a speaker), not about rocket science!
In the pro world it IS a big marketing argument.
 

morricab

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No I am assuming any transient in acoustic music. Again, if such compression existed it would be very easy to measure. The high-efficiency manufacturers are surely competent enough to do it and if proved it would be a fantastic marketing argument. Or do you think they can't handle measuring instruments?

Remember we are arguing about a measurable simple electrical effect - the dynamic change of value of a resistor (the coil of a speaker), not about rocket science!
You are also talking about physics but what about perception...that is even beyond rocket science!
 

morricab

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No I am assuming any transient in acoustic music. Again, if such compression existed it would be very easy to measure. The high-efficiency manufacturers are surely competent enough to do it and if proved it would be a fantastic marketing argument. Or do you think they can't handle measuring instruments?

Remember we are arguing about a measurable simple electrical effect - the dynamic change of value of a resistor (the coil of a speaker), not about rocket science!
measuring jitter down to femtoseconds is also not a problem as is distortion down to -140dB but with both it is not clear how we A) can perceive effects so small and B) how exactly these perceptions are impacting the sound but it is not pretty well accepted that very small effects can have significant impact on the perception of the sound.
 

microstrip

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In the pro world it IS a big marketing argument.

Exactly my point. They listen extremely loud in very large spaces. Audiophiles do not have such problems, but surely can imagine them - poorly designed speakers suffer from it. But it is not a concern with the quality speakers often referred in these WBF pages.
 

microstrip

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You are also talking about physics but what about perception...that is even beyond rocket science!

Sorry you were clearly addressing physics - thermal compression. Perception only applies after we have a physical difference. ;)
 
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microstrip

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measuring jitter down to femtoseconds is also not a problem as is distortion down to -140dB but with both it is not clear how we A) can perceive effects so small and B) how exactly these perceptions are impacting the sound but it is not pretty well accepted that very small effects can have significant impact on the perception of the sound.

Again, as you say, we measure the differences ... Any way, jitter and THD are just two old classical parameters that are extremely limited and impossible to correlate effectively with the effects of very small non linearity. Designers have proper custom measuring techniques but they are proprietary. The current Audio Precision analyzers have advanced modes and can be configured to carry many non standard measurements. They would easily measure transient thermal compression ...
 

morricab

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Exactly my point. They listen extremely loud in very large spaces. Audiophiles do not have such problems, but surely can imagine them - poorly designed speakers suffer from it. But it is not a concern with the quality speakers often referred in these WBF pages.
This where we disagree…I think it does affect most speakers, including wry expensive ones. Hearing speakers that truly have higher dynamic limits (not loudness limits) spoils one for speakers that sound clearly less capable dynamically. IMO, even very large cone speakers sound less dynamic overall than a good horn loaded single driver…just that the single driver will be probably quite uneven in that dynamic as a function of frequency. This is why I prefer at least a high sensitivity two-way so the dynamics are more evenly balanced over the frequency range.
 

morricab

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Sorry you were clearly addressing physics - thermal compression. Perception only applies after we have a physical difference. ;)
There are clear measurable differences this is demonstrated clearly in the links I provided and many others I didn’t. The question then becomes about perceptibility and what impact that has on the realism perception.
 

Ivo

Member
The 8 most import factors for dynamic compression in reproduction of a musical event are:
1. The recording
2. The applied driver's total suspension compliance and linearity vs its dynamic output in its dedicated bandwidth.
3. The enclosure vs various compliance factors of the driver
4. The waveguide/horn vs driver and/or waveguide vs overall baffle shape/covering.
5. The self-induction of the driver and its linearity over excursion.
6. Driver's thermal and magnetic saturation linearity.
7. Thermal effects regarding air inside enclosure, and in room.
8. Matching linear driver compliance to desired dynamic range.

1.The recording
As we all know, some recordings play louder than other, while using the same total dynamic range. This highly depends on the compression of the microphones used, and the amount of gain compression, limiting and other tools that have been applied by the producer and mastering engineer. For us the best recordings are made with top notch microphones and studio monitors, or even better: high end speakers, to resemble the quality of our high end equipment being equally low in dynamic compression.

2. The applied driver's total suspension compliance and linearity vs its dynamic output in its dedicated bandwidth.
The driver's moving parts will be relatively harder to move when making larger movement. This starts with the QMS factor of a driver (eg. a softer spider and more flexible rubber surround) to provide a constant level of compression (this also applies to microphones). But then, most important for DYNAMIC compression, is its kms linearity (actual compliance, when inverted it is the cms number of the driver).
Good:
StillasubKms.PNG
Bad (for this example, I compared a competion driver of the same size):
1670529660331.png
Basically the flat and symmetric (from 0) part is the part of excursion in mm that is without dynamic compression. Typically seen is a lot of dynamic compression in mid-range drivers on perhaps more pop/mainstream focussed speakers (B&W 800, KEF blade etc.) that don't apply a decently flexible surround around the membrane, allowing it to move freely. With such speakers, the louder you play, the more energy is relatively NOT used to larger parts of the output, so not ending up in the same relative air movement when comparing large sounds to small sounds (the small sounds, details, high frequency sounds, get highlighted). If the mid-range is relatively harder to move on larger excursion then bass and high frequency drivers, you get a "smiley curve" when playing loud. With simultaneously compressed detail entering the mix in mid-range.

These will sound good or (escpecially accaptable and forgivng) on mixes made for pop/radio or mixed of on something like is mixed off on short/mid-fields like eg. Genelec 8351 (which is however a very decent monitor for soundstage-checks), instead of doing so with proper main monitors such as found at the same brand in the SAM range. If you personally agree will still depend taste and finesse. Many might prefer this mid-compression behaviour, pending on the overall speaker dispersion vs room situation and personal taste. Personally I like a speaker that sounds such as good and in balance with low and high volume, including all frequency bands, and only sounds even better when considering the typical effect of the natural extra's pure db's being brought to the table (my ears). It also means that for top tier, we need to go for multiple drivers, each optimal in their own specific bandwidth application. And it has to sound right anywhere from fair living room system situations to top-tier-listening rooms.

The type of driver also is very important: Ribbon's, electrostatic panels, AMT's all have typically (but not necessarily) more dynamic compression than a membrane placed relatively free in a high QMS suspension (dynamic driver, moving coil), given there constructive nature. But also a compression driver, although having a more typical (inverted) dome membrane, usually depends on this type of higher-loss and less-linear suspension (wiki):
1670531250492.png
But there are more ways to low-compressed-Rome, if also counting other driver and enclosure, even taste, parameters: Its a about the mix being optimal towards the listener, more than what type of road/direction to choose.

3. The enclosure vs various compliance factors of the driver
Typically larger enclosures for the same size driver add less dynamic compression. But this highly depends on other parameters and if there is any tailoring/adjustment opportunity in the electronics (preferable analog room-adjustments for high end applications). A dipole driver might at first seem the solution, if it where not that to cope with the VASTLY higher amount of excursion needed for the same sound level output. Hence, all dipole's come with stiffer and usually less-linear types of suspension and when comparing it for dynamic compression linearity, its not easy to match output AND linearity to dynamic drivers with dedicated enclosure. In the end only a very very large amount of dipole membrane surface can compete with a driver placed in an enclosure (with its compression effects being typically far more linear than any type of mechanical driver-integrated suspension is). One or the other can be compensated by DSP, but speaking of high end, not one of such applications has convinced me up to now (and yes we also did a lot of R&D on this DSP path, as its easier to work with digital than analog, but still we feel to go for analog for top tier applications, if not already only for not adding a A/D D/A path that will always come short to the latest and best DAC/server, let alone turntable nqualities we cherish to consistantly upgrade to).

4. The waveguide/horn vs driver and/or waveguide vs overall baffle shape/covering.

Compression drivers can sound ok in balance, if coming with a next-level type of suspension, and when being placed in a modest horn/waveguide. But please don't assume that a horn, when going from small to big "decompresses" the sound from the compression driver. No, au contraire, anything that is not just plain free baffle compresses sound. So a compression driver does a lot of this, and you have to add the waveguide/horn on top. To explain it simply: if sound can still bounce up and down before it goes out, it compresses. So more detail, yes, but less balance.

Speaking of dynamic compression, we ideally we see some freedom of movement on the compliance part of the driver, no need for a compression driver unless wanting crazy SPL gain (PA, or with let's say 2 watt DHT SET). In the end, with most horns, we cannot expect sound to be the same as the original happining (acoustic concert) or intention of the mastering engineer (using probably not horn monitors). We can reach a desirable status quo with electronic pairing, but with dynamic compression added to the mix, playback volume soon becomes more important than it should or could be.

We do can expect the mastering engineer to use wave-guides and here also the baffle has a role: sharp edges will dynamically compress all sound compared to those fitting the dimensions of the baffle. Hence a baffle should be as small as possible, have rounded of/slanted edges, or be completely rounded over its front face (working well only with the appropriate room, since energy is now redirected to walls rather than to the listener, and speed of sound, now more also non-direct will appear lower or a touch more smeared). Or better still: have a damping material covering it to compensate the applied waveguide effect (We do so, but also see Wilson, Rockport etc.). All other effects in balance of speaker output vs room vs mastering studio conditions should be handles in the filter (a flat curve on-axis, or especially 15 or 30 degrees, will only sound good in a studio, not a top-tier listening room).
 

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Ivo

Member
5.The self-induction of the driver and its linearity over excursion.
Drivers can waste a lot of energy in non-usable effects. There is the self-induction of the driver combined with the relative amount of energy going into eddy currents, and the overall linearity of these inductive effects over small to large excursion is a defining parameter when considering dynamic compression. Hence, if we want less dynamic excusion we want to minimize these effects. There are all kinds of things to use, such as symmetric driver, FEA optimized magnet dimensions/shapes, copper and alu shorting rings, hexagon/super-dense coil winding, material of coil former, etc etc. Too much to explain here now right away, but questions are welcome.

An excellent truly-symmetric driver (using a lot of additional magnet/constructive material and copper, hexagon winding and fully saturated magnet):
Inductance-over-current-LX0-I.png
An equally excellent driver using FEA motor and shorting rings and special coil former material (see for comparison to above only +-7mm on the bottom scale):

20180306175737_Figure9-ScanSpeak4578T00Subwoofer.jpg
The second is a bit lower in overall self-induction, but a bit less linear. Both have the ingredients to sound top-tier in larger driver's. In smaller driver's sound the flatness becomes more important, and a even far lower amount of self-induction is desirable. And no, it also doenst come done to choices such as underhung vs overhung. It's far more complex than anything of such black and white comparisons.

6. Driver's thermal and magnetic saturation linearity.
A driver with good saturation will be more linear in point 5, but also thermally. In general, the motor should be big enough to handle big currents, before eddy currents start to f-up linearity. As for tweeters, its nice to use a driver here that has far more headroom in terms of both thermal capability as well as linearity for all excursion parameters.


7. Thermal effects regarding air inside enclosure, and in room.
Air compression is on a logarithmic scale between Pressure and Volume, see ideal gas law curves going from low to high temperature (wiki)
View attachment 101348
We want all parameter to stat in the flat bottom scale. Higher temp, makes the bend of V vs P bigger, so less linearity to be found. A common problem is happening when having the amp in the same enclosure, like many subs do: warmer means less linearity to be found under the same volume levels. Same goes in a way for tweeters being pushed hard, as they have typically there own chamber. It helps to have tank-type tweeters that are fast because of their motor-specs, and apply dual chambers (like we implement). But also, in general (subwoofers, woofers, mids), closed box can warm up more than reflex, when speaking of output vs temperature with the same driver size.
Furthermore: membranes might also behave far more different that you typically might expect at different given ambient room temperatures.

8. When playing loud: matching driver compliance to desired dynamic range.
There are many parameters to consider(too many to all discuss in this post), but perhaps the most important is the BL linearity, or 'forcefactor' in Teslameters. This tells how the motor can control the motor. Does it give the same force/control for low volume sounds as big volume sounds?
Good:
BL_compliance.jpg
Bad:
BL_BAD.png

All the same applies for virtually all electromechenical drivers. How much air does it needs to move while staying linear, will in the end define it what bandwidth we search the parameters to comply to and be engineered/optimized to excel in. The more consistent (flat, symmetrical for both in and outwards movement) it is within that band, and without any aspect spoiling the other, the better it will enable us to get minimum dynamic compression, and if you ask me, the best possible reproduction, especially if money is no issue. Mostly we see compromises. Eg: the lack of putting a midrange surround on a driver also helps to surpress distortion (eg the KEF blade are impressively low in midrange distortion). But a compromise still it is. We want speed in the motor, not in the membrane. We want distortion to be low in both motor and membrane, even without holding a firm compressing grip on the latter.

Conclusion:
What speaker type you like, depends on your taste. It can be dynamic driver, ribbon, amt, electrostatic planar, segmented or not, suspension or not, compression, horn, waveguide, fully-round baffle vs wool-covered baffle, large or small etc. But even if you like one type most, you might still see that other approaches are almost just as satisfactionary, if well-engineered. In the end, I prefer thoroughly engineered dynamic drivers that are low in distortion without needing low room-of-movement, and with full un-compromised linearity (meaning also lowest possible dynamic compression) in their usable range for my favorite audiophile recordings (including both very low as very high playback volumes), or full unspoiled orchestras's recorded on very good mic's with no compression added later, but also when using them for 50's jazz, phychedilic rock or the latest and very compressed techno at partylevel.

Still I also see some panels doing a nice thing for me if segmented and allowing certain linear movement, or even horns (Avantgarde top level. comes to mind). Perhaps this, although a bit technical, answer gives some insight, even without full understanding, how so many parameters have to work together in the end to be resulting it what we should consider "what's best".

Well now, what does this help for the topic starter or others considering the negative effects of dynamic distortion? To see that only if the manufacturer can provide the total amount of parameters affacting dynamic supression, you can make an educated guess on how special or next-level-good this is. One highlighted parameters does not garantuee anything at all. And I hope this post can, if not helping to make choices, do at least a micro-addition into the shared bucket of awareness to whats at play and that -even if your favorite brand doesnt do so- you on your turn make better decisions on what to try next...
 

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godofwealth

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These ideas were explored a long time ago in the mid 1950s by Paul Klipsch, who in my mind ranks as one of the two best speaker designers ever (the other being Peter Walker who designed the legendary Quad electrostatics). Paul spoke at length of the importance of speaker efficiency in controlling distortion, particularly what he called FM distortion. Paul’s sage words and wisdom, alas, have been forgotten by the vast majority of modern speaker designers. Even the M2 line of JBL fails to realize the importance of horn loaded woofers. The distortion of the M2 is unacceptably high in my view, given its cost, as Erin’s measurements show. The Klipschorn and La Scala have far lower distortion at 100 dB than the M2, about 20-25 dB lower. The Quads can manage to produce low distortion in the upper mid bass and above, but only till around 95 dB, snd then they shut down.

There‘s no free lunch in speaker design. You have to choose your design objectives and the compromises you make. You can’t achieve low distortion in a bookshelf loudspeaker that has very low efficiency. The much ballyhooed Kef LS50 Meta is raved about in audio rags like Stereophile. Take a look at its distortion below even at moderate volumes (measurements from ASR). In the bass it’s a nice distortion generator.


1675303097223.png
 

adrianywu

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These ideas were explored a long time ago in the mid 1950s by Paul Klipsch, who in my mind ranks as one of the two best speaker designers ever (the other being Peter Walker who designed the legendary Quad electrostatics). Paul spoke at length of the importance of speaker efficiency in controlling distortion, particularly what he called FM distortion. Paul’s sage words and wisdom, alas, have been forgotten by the vast majority of modern speaker designers. Even the M2 line of JBL fails to realize the importance of horn loaded woofers. The distortion of the M2 is unacceptably high in my view, given its cost, as Erin’s measurements show. The Klipschorn and La Scala have far lower distortion at 100 dB than the M2, about 20-25 dB lower. The Quads can manage to produce low distortion in the upper mid bass and above, but only till around 95 dB, snd then they shut down.

There‘s no free lunch in speaker design. You have to choose your design objectives and the compromises you make. You can’t achieve low distortion in a bookshelf loudspeaker that has very low efficiency. The much ballyhooed Kef LS50 Meta is raved about in audio rags like Stereophile. Take a look at its distortion below even at moderate volumes (measurements from ASR). In the bass it’s a nice distortion generator.


View attachment 103807
Yes, but research has shown that below 200Hz, distortion level of <10% is not perceptible by the human brain.
 

Ivo

Member
In our research this (audibility of distortion) is proven to be highly depending on frequency, room, playback-volume of the original signal, type of recording or test signal, listening distance, system and phase/time effects, and most of all, the listener herself: A trained listener can easily detect h2 of 1% and h3 of 0,5% in certain double blind tests of our high end test-systems in our auditorium at moderate listening levels. Depending the above parameters, this can be as low as under 0,5% and 0,3%. In the system we "staple" distortion, where the driver is usually the highest provider of distortion. In that sence, you can see that de KEF example above is definitely in trouble below 200hz, although as we move farther down and get very low in frequency, the treshold definately goes up (but not nearly as fast as such a small driver is keeping up with, even at lower listening levels). Thats why they (KEF) have a blade model for that. However, on topic, these kef drivers are a bit high in dynamic midrange compression, by of lack of cms/kms linearity (no low-loss rubber surround applied here).

The total result, of the entire system (electronics, drivers, cabinets and even room) has a certain behaviour of distortion types and mixes, not only even harmonic distortion vs uneven, but also inter-modulation (more easily detected and bad-sounding than harmonics)) and phase-shifted distortion types, and all allowed to different levels combined at very very differently mixes per frequency, and also needs to be also dynamically reviewed together with counter-effects of certain choices. As godofwealth said: there is no free lunch. So the KEF topology discussed here has very low distortion, of levels that can be considered to be "high end" in the midrange, but thats actually quite easy if not allowing a lot of movement of the membrane. In fact, we might state that (some) distortion is exchanged for (some) dynamic compression.

So, in the whatsbest area, we tend to keep distortion below the tresholds coming out from our research without doing so with applying the method of less movement/no-surround/free-movement, in the most ideal harmonic/phase mix and engineered, and thus so with different listening levels and compression fully in mind. That is a big amount of work, but in the end gives the best outcome of electronics pairing and ultimately the best sound quality possible, at the biggest scope of nice to top tier recordings. To make it even more complex, you ideally test this with a variety of top notch rooms and systems: listening tests always prevail over how to we should understand and finetune (and move ahead in) theoretical approach while developing speakers.

With today's latest and best driver tech fully applied and both FEM computing (designing drivers) as well as large signal laser measurements as a development tool and all telling software in our hands, it has become possible to do it right, if at least capable of also engineering the cabinet without resonance and other flaws, without using horns. Some of the best high end speakers started to show this, and do so without the 'less-good' effects of compression and time-smearing associated with horn-loading. That brings us today (finally) in to a totally different paradigm, compared to the 50's. But yes, even in high end, we see a lot of "bad" engineering still, and well executed horns (that also have a come a long way since then) might still sound better than those examples.

Some whatsbest listeners might simply like, or are quite solidly tuned into, the dynamic and directive horn behaviour (extended detail and easier room-interaction). It is in my modest beliefs, that a simple waveguide on a large tweeter for the lower highs is all we need these days if this driver, and all other drivers of that loudspeaker, are top notch and well time-aligned/filtered and paired with a top tier (but not too extensively treated-) room, and system. We all have a high-end friend or two that is not picking up on any change from there favored topology (electrostatic panels, horns or something else), and I also very much like some of the better ones, but times are changin'.
 

morricab

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In our research this (audibility of distortion) is proven to be highly depending on frequency, room, playback-volume of the original signal, type of recording or test signal, listening distance, system and phase/time effects, and most of all, the listener herself: A trained listener can easily detect h2 of 1% and h3 of 0,5% in certain double blind tests of our high end test-systems in our auditorium at moderate listening levels. Depending the above parameters, this can be as low as under 0,5% and 0,3%. In the system we "staple" distortion, where the driver is usually the highest provider of distortion. In that sence, you can see that de KEF example above is definitely in trouble below 200hz, although as we move farther down and get very low in frequency, the treshold definately goes up (but not nearly as fast as such a small driver is keeping up with, even at lower listening levels). Thats why they (KEF) have a blade model for that. However, on topic, these kef drivers are a bit high in dynamic midrange compression, by of lack of cms/kms linearity (no low-loss rubber surround applied here).

The total result, of the entire system (electronics, drivers, cabinets and even room) has a certain behaviour of distortion types and mixes, not only even harmonic distortion vs uneven, but also inter-modulation (more easily detected and bad-sounding than harmonics)) and phase-shifted distortion types, and all allowed to different levels combined at very very differently mixes per frequency, and also needs to be also dynamically reviewed together with counter-effects of certain choices. As godofwealth said: there is no free lunch. So the KEF topology discussed here has very low distortion, of levels that can be considered to be "high end" in the midrange, but thats actually quite easy if not allowing a lot of movement of the membrane. In fact, we might state that (some) distortion is exchanged for (some) dynamic compression.

So, in the whatsbest area, we tend to keep distortion below the tresholds coming out from our research without doing so with applying the method of less movement/no-surround/free-movement, in the most ideal harmonic/phase mix and engineered, and thus so with different listening levels and compression fully in mind. That is a big amount of work, but in the end gives the best outcome of electronics pairing and ultimately the best sound quality possible, at the biggest scope of nice to top tier recordings. To make it even more complex, you ideally test this with a variety of top notch rooms and systems: listening tests always prevail over how to we should understand and finetune (and move ahead in) theoretical approach while developing speakers.

With today's latest and best driver tech fully applied and both FEM computing (designing drivers) as well as large signal laser measurements as a development tool and all telling software in our hands, it has become possible to do it right, if at least capable of also engineering the cabinet without resonance and other flaws, without using horns. Some of the best high end speakers started to show this, and do so without the 'less-good' effects of compression and time-smearing associated with horn-loading. That brings us today (finally) in to a totally different paradigm, compared to the 50's. But yes, even in high end, we see a lot of "bad" engineering still, and well executed horns (that also have a come a long way since then) might still sound better than those examples.

Some whatsbest listeners might simply like, or are quite solidly tuned into, the dynamic and directive horn behaviour (extended detail and easier room-interaction). It is in my modest beliefs, that a simple waveguide on a large tweeter for the lower highs is all we need these days if this driver, and all other drivers of that loudspeaker, are top notch and well time-aligned/filtered and paired with a top tier (but not too extensively treated-) room, and system. We all have a high-end friend or two that is not picking up on any change from there favored topology (electrostatic panels, horns or something else), and I also very much like some of the better ones, but times are changin'.
And yet the pro world doesn't really agree with you...
 

Ivo

Member
But there is a reason why we go to waveguides only in studio. Or even to high end consumer speakers at the master for best results.Four different cases: 1)whatsbest listening room, 2)high-end studio/mastering, 3)studio, 4)PA concert. The overlap is smaller than you think (or bigger than you might think when comparing the best audiophile recording situations with whatsbest listening room).
 

gleeds

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May 29, 2018
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Morricab, I agree with many of your points concerning the advantages of horn speakers. When properly executed I love them. Two years ago the best sound of the Florida Audio show for me was a set of relatively affordable two-way horns from Blumenhofer powered by a brilliant 8 watt/channel 300B SE amplifier from Takatsuki. The near complete absence of compression and gorgeous tone were captivating. This contrasted against monster, mega dollar systems displays from the biggest players that simply could not compete on realism and emotional engagement.

As I read Ivo's treatise on the subject, it's clear he has no bias against horns, and as I do believe them to be outstanding in certain areas and essential in others. My priorities in loudspeakers go something like this:

- lack of dynamic compression
- low distortion
- a coherent wave launch ala coaxial designs (but without the dynamic limitations many but not all exhibit)
- well saturated but not overly ripe tonal palette

Given Ivo's scientific approach to loudspeaker design and his research into advanced cabinet materials and drivers I believe AEquo is able to achieve what's best from all designs (horns, electrostatics, planars and multi-way dynamics). For this reason I have chosen to invest in representing AEquo in North America over all other products available to me.

Toward the end of 2023 AEquo will be introducing a groundbreaking new loudspeaker design, the first of many to follow incorporating everything Ivo has learned from his considerable research and time invested into the limitations various loudspeaker designs express (especially when placed in the listening room) and the challenges each imposes on our enjoyment of music.

Having said that - long live horns!
 

Ivo

Member
Thanks Gary. :) And indeed, the horn loading concept still has a lot going for it and although this topic was specifically about dynamic compression and therefore had some criticism from my side on that single aspect, I really really love some well executed horns (worked on some and had some too (one system-example I like comes to mind to add here, for it also fits the talk about distortion: Avantgarde Trio with Audiopax m50/m100; 12AT7/kt88's and "timbre select" for adjusting the HD profile, not easy to get right, but can sound amazing). So also from my side: Long live horns (and I am sure they will, not just in PA systems)!
 

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