Why not horns?


I've owned a lot of speakers over the years but I have never experienced anything like the midrange reproduction from my horns. With a frequency response of 300 Hz. up to 14 Khz. from a single distortionless driver, it seems like a no-brainer that everyone would want this performance. Why don't you use horns?
macrojack
Unsound likes Thiels and hates horns. Let's be honest, would anyone who prefers the presentation of Thiels ever appreciate what a good horn system can do? I really doubt it.
Actually, despite their huge differences in design, I suspect a good set of horns might be fine tuned in a manner to not sound all that different, but I doubt that this would be the case if left to chance.

I also think the horns could be tuned to sound like many other different sounding designs as well, like Harbeth, if that is the intent.

I believe that the sensitivity of horns can be either their bigbest strength or their achilles' heel. Its all in the overall sonic recipe. A little too much salt or pepper can have a magnified effect.

I always go back to thinking of horns (done well) as putting the sound under a microscope, for better or for worse. Otherwise minor differences in signal can now produce major differences in resulting sound.

To me, you better have a love or fascination with horns if you are going to voluntarily deal with them. If you do not have the desire to do what is needed (which may be a lot) to get things right, better off staying away.

That to me (along with size requirements) is probably the best answer to the question "why not horns?".
05-29-10: Herman
Macro, you are a bit off base on that one. It is one of the common misconceptions in audio. Your description of being physically aligned is correct but your description of phase and polarity isn't.

A difference in phase means a difference in time. A difference in polarity means one signal is going positive while the other goes negative. Phase and polarity are two entirely different things.

It is confusing because if you reverse the wires on one speaker (black to red) in a stereo pair then everybody says the speakers are out of phase. That is technically incorrect. The correct phrase is you have reversed the polarity to one speaker. One will be going in while the other is going out. They still happen at the same time so they are in phase but they move in opposite directions so they have opposite polarities. Unfortunately it is common practice to describe it as the speakers are out of phase, and it is awkward to say that one has its polarity reversed, so we are stuck with a phrase that is technically incorrect.

Same situation with balanced cables. While one line is going positive the other is going negative. Some people incorrectly say they are out of phase but actually one has inverted polarity.

If the speakers arenÂ’t time aligned then there is indeed a phase shift, a difference in time.
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Huh?

Herman,

Phase is an relationship , when you reverse the polarity of one speaker you change the phase , hence they are no longer in phase. This is of course completely different from acoustic phase, as you described , but considered electrical phase....

Regards,
All that we are talking about with horns is mechanical amplification. As with electronic amplification, it can be good or bad, clear or distorted. Would you condemn all amplifiers as honky, distorted or shrill just because you heard one that deserves that description?
In many respects horns are in their infancy. I believe that many of the objections, particularly size and price, can be mitigated by motivated entrepreneurial experimentation and careful research. This being done on a small somewhat random and utterly uncooperative scale by isolated hobbyist/inventor types. A few, like Bill Woods, have made it their life work. Perhaps, if serious efforts were made by established firms like Klipsch and JBL
we would see real progress in this area. However, what is to motivate them if we continue to tell them we want poor sounding, slim compromised sculptures? If we can emerge from our self-imposed darkness and begin to learn about the potential hidden promise of horns, then there is no telling where it might lead us.


Well they are not my kind of speaker and have not listen to one in quite sometime. I do get the opportunity to do so this weekend and with custom amplification to boot!

Stay tuned!
Re phase and polarity, I believe the reason for the ambiguity and inconsistent use of the term "phase" is that a delay or phase shift mechanism can be either phase dispersive (affecting the phase of different frequencies differently), or phase non-dispersive (affecting the phase of all frequencies equally).

A polarity inversion is the same thing as a 180 degree non-dispersive phase shift. An arrival time difference caused by multiple drivers whose physical placement is not time-aligned relative to one another would be a dispersive phase shift.

Regards,
-- Al
macrojack,

I like your assertion that horns are essentially a form of mechanical amplification that can be done well, poorly, or anywhere in between.

Unfortunately, my gut tells me that practically mechanical amplification is a preferred means of the past and not the wave of the future.

More efficient forms of electronic amplification, like Class D switching amps. are the wave of the future and will likely put an even further hurt on high efficiency speaker designs, horn or otherwise.

BTW, I do own a pair of horns. One of them can be seen in one of my system photos. Take a look and see if you can find it!
Macrojack, I think you make a good point. I think electrical amplification is preferable. As I posted earlier, I suspect that the current trend in horn speakers, is due to the current trend in low powered amplifiers, not to any inherent superiority of horns. I will grant you that horns almost always play louder, and are usually superior in dynamic contrasts. To my ears those benefits are far out weighted by their compromises. If mechanical amplification is all that good, why aren't Victrolas used much anymore?
I own a klicpsh 5.1 set up which I listen in six channel set up or in two channel stereo set up and they sound very lively. For those who listen to hard core Salsa music this is the only way to go.The sound production will put you on the dance floor weather you are a dancer or not.Plain and simple.On the other hand, if I just want to do critical listening I go to my Ushers.Horns give you the opportunity to feel crochendos,decrochendos,accents as if you were in a club listening to live music.When I listen to Tito Puente on timbale drums I am able to disect his rymthm patterns in SUPER detail.Its imposible to do it with non horn speakers.The same goes with the other latin drummers.Hand slaps rolls finger slaps ruffels etc.can be distinguished perfectly. I personnally use the horn to study my drumming.I just can not do this with non horn speakers.If there is something that you spectifically look for in a musical piece you just might fine it with the horns.Bottom line ,you just have to listen to them to see if they favor your type of music.
I think we can all agree that horns are not going to set the mainstream audio world on fire anytime soon. But I believe it is NOT because of mechanical amplification being outdated. (Are we now going to claim that tube amplification is old technology and outdated?) Most designers don't understand how to work with them. Then there are the drivers. Many horns, including the ones I use, are built with vintage, pro drivers in mind. Except for my Fostex horn tweeters which are very recently made. There are shipping issues, user issues, WAF issues, etc., which are all valid reasons why there are not more horn speakers being designed these days than this old and in the way technology theory.

Victrolas? Bad analogy. Just because those had a horn does not make it work in this comparison. There are many, many more issues with those old gems which would speak to why they aren't used anymore. If we all remember, those things had no electronics and you cranked them by hand.
Horns have greater potential than any other approach. Designers who move into using horns do not go back unless they need the money they can make producing yet another boring rendition of the 3-way.

Dan-ed,

Those other issues you mention are some of the reasons why physical amplification (ie horns), which is one of the older audio technologies out there, have largely fallen out of popular favor and been replaced by other approaches. Isn't that pretty much what outdated means?

Tubes versus SS amplification is not a relevant analogy because the pros and cons of each of those approaches are totally different than those associated with electronic versus physical amplification in general.
06-03-10: Almarg
Re phase and polarity, I believe the reason for the ambiguity and inconsistent use of the term "phase" is that a delay or phase shift mechanism can be either phase dispersive (affecting the phase of different frequencies differently), or phase non-dispersive (affecting the phase of all frequencies equally).

A polarity inversion is the same thing as a 180 degree non-dispersive phase shift. An arrival time difference caused by multiple drivers whose physical placement is not time-aligned relative to one another would be a dispersive phase shift.
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Hello Al,

All true , but the word Phase describes a relationship it can be applied to anything really.

regards,
Macrojack, why would "Horns have a greater potential than any other approach."?
No, horns are THE OLDEST form of amplification. ;-) I'm not sure if they ever were all that popular in home audio. It can be argued that they were somewhat of a necessity before we had better amps. And the first electric amplification was with tubes so that technology, while ages younger than mechanical amplification, is considered outdated by many people today. But that is only their opinion. Both of these technologies do still work, and work well.

The average audiophile will not consider pro-audio anything because of a bias instilled by countless years of reading audio magazines. Horns seem to get lumped in with pro-audio, even though there are many horn designs that don't use pro drivers. No, I don't think the shift is due to outdated technology. There are quite a few designers today who use horns.
I think pro-audio got the balanced standard thing right. But they sure are ruining popluar music recording.
Unsound - Horns are the least exploited speaker technology out there. They are capable of lower distortion, greater dynamic contrast and quicker response. The combination of low mass and high output allows them to provide explosive sound and minute detail concurrently.
And does anybody think that horns are any more archaic than cones? The dome tweeter and conical midrange have been worked every way they can be and the last ounce of potential was wrung out of them long ago. Acoustic suspension is a parlor trick that can buy some compactness at the expense of speed, explosiveness and efficiency.
Horns are not yet well understood but the curtain is rising slowly and, I believe, we are nearing the threshold of a breakthrough in popularity which will create better and cheaper product. Maybe smaller too.
"why would "Horns have a greater potential than any other approach."?"

I'm in agreement with you on this question, Unsound. I gather from Microjack's most recent reply that he may be referring to the general masses, rather than what is already known by those who have studied horns for years.
Macrojack, horns have have historically had some of the biggest companies spending the most money trying to develop them. I don't see why you think they are capable of lower distortion. Yes, I think horns are more archaic. There's a reason there are so many more cones and domes, they make more sense. Even panels and omnis make more sense, at least to me. Speaker designers no longer need to compromise their products due to the limited availability of high powered amplifiers. Other speaker designs are capable of filling residential sound rooms with enough volume without the need for additional mechanical volume enhancers. Horns have been well understood for decades. Perhaps there might be advancements due to CAD, improved drivers and digital cross-overs, but those types of advancements will be probably bear more and sweeter fruit for other designs. Truth be told, many if not most of the advancements that might be available in horn development for home use, will probably never see the light of day, because they probably aren't worth the investment due to market considerations. What ever future horn development there might be, will probably be geared to commercial venue applications in which high fidelity might not be the highest priority.
Unsound wrote:

"Macrojack, why would 'Horns have a greater potential than any other approach.'"?

Well I'm not Macrojack, but I did stay at a Holiday Inn last night...

Okay, my design experience is limited to systems that use a direct radiator woofer and a constant-directivity-horn (or waveguide)-loaded compression driver. Focusing on the horn section, here are a couple of inherent advantages as I see them:

1) Well-controlled radiation pattern, which results in a reverberant soundfield that has very nearly the same spectral balance as the first-arrival sound. Not all horns do this, but constant-directivity ones have this potential assuming you get a few other things right. Live sound sources usually result in very little spectral discrepancy between the first-arrival and reverberant energy, but most speakers fail to preserve this relationship. I think it matters because, in most listening situations, most of the energy that reaches our ears is reverberant energy.

2) Presevation of dynamic contrast due to negligible thermal compression at normal in-home listening levels. This can actually be detrimental if the horn is not paired up with a woofer that has similar characteristics; if the woofer compresses and the horn doesn't, then the system sounds brighter and brighter as the volume level goes up. But when the dynamic contrast in the recording is properly preserved (including correct tonal balance regardless of loudness level), the emotion that the musicians intended is more effectively conveyed because musicians often use dynamic rise and fall to convey emotion.

Disadvantages include:

1) Coloration. This is a complex subject, and briefly all horns produce coloration of some type, but not all horns are equally objectionable in this regard, and some types of coloration can be dealt with in the crossover. The best horns minimize those colorations that cannot be readily addressed by the crossover, and then the crossover does the rest. Unfortunately reduction of coloration to negligible levels by a properly designed and implemented horn cannot be proven in an internet forum post, so this subject is hotly debated. My comment here would be, just as not all cones or domes or ribbons are created equal, so too not all horns are created equal.

2. Challenging crossover design. With rare exception, horns call for fairly complex crossovers in order to minimize their colorations and provide a smooth transition to the woofer section. Those few horns that are exceptions are not constant-directivity types, and thus do not have the reverberant-field characteristics that matter in my opinion. Some people hold that complex crossovers in and of themselves are bad, and this I disagree with; as long as the crossover does its job unobtrusively, the component count has no audible consequence.

If horn colorations can be reduced below the audibility threshold, and if dynamic contrast and the reverberant field really do matter, then a good horn system offers worthwhile advantages over a conventional system. I think the colorations can be rendered insignificant with proper system and crossover design, to the point where a good horn system is quite competitive with conventional systems in the same price range. But I think one has to start with a very good horn to begin with, as most horns have audible problems that cannot be solved by the crossover.

In general smaller horn systems need less distance to "focus" than larger ones do; one of my customers was listening to one of my systems (10" woofer + 10" round waveguide) at slightly more than arm's length, with (to my surprise) no audible problems.

Now it might be possible for a conventional speaker to match the thermal compression charactics of a good horn system, but at a higher price. And I do not know of any low-cost techniques of radiation pattern control that are as precise as what a well-designed horn or waveguide can offer in this regard. That being said, I think a good planar system that inherently has good radiation pattern uniformity can also be pretty spectacular, but that's a different topic for a different thread.

Duke
Duke, thank you for your thoughtful response. It has been argued here that that though they might appear similar that wave guides and horns are different enough as to require them to be categorized differently. Wouldn't such a controlled radiation pattern reduce the size of the sweet spot and reduce the sound-stage, especially for multiple listeners? I've not heard this to be the case with horns. Wouldn't the amount of reverberant sound be greater in most indoor live venues too? So long as the reverberant sound is not too close in time, shouldn't we be able to hear this as a reverberant sound and not as distortion? Furthermore, couldn't this reverberant energy be controlled via room treatment and/or room correction? If my budget permitted, I'd guess that I'd move from cones & domes 'n boxes to top quality omnis. Perhaps the antithesis of what you've described as an advantage. Aren't there already existing remedies for such thermal compression in many cones & domes and not really much of an issue for alternative drivers? Am I correct in assuming that the cross-overs you describe aren't digital and therefore are probably incapable of preserving correct time and phase? It would appear to me that this ideal matching of non-horn loaded woofers to the rest of the horn loaded drivers must be rare in deed, all the horn loaded systems I've heard are blaringly bright. I have still yet to hear a horn system that's colouration's are below audibility.
One thing that Duke did not cover is the drivers in use in the horns. Many speakers have breakups which contribute to distortion; if a horn driver exhibits this the result can be really bad. I know of at least one driver that has no breakups in the passband (its a true beryllium dome) and is helped by a kapton suspension that prevents artifact at the edges of the passband (250Hz-12KHz). This driver is very fast, very detailed and very smooth.

The other area that can be a problem is the interface of the driver to the horn- the throat area. The 2" TAD driver and 500Hz machined maple horn were an excellent example of this problem- right at the crossover/passband limit there was a peak followed by a dip before it smoothed out and it was not pleasant.

BTW this was in the Classic Audio Loudspeakers up until about 2 years ago when a new horn and driver (field coil) was introduced that fixed that problem (Valin gave the new driver on the old TAD horn Best Sound at Show and a few months later when the new horn was added declared that the new horn/driver combo was 'the biggest improvement he had heard in any speaker'). Its a fact that CAD has helped out horns immensely!! TAD **has** to have known about that problem but over the years/decades they did nothing about it.
I think that the potential for dynamics is the main attraction of horns to most, including myself, all other things aside.

Plus I do think they are cool looking.
FWIW, I find most horns ugly, but the Avant Gardes while not my cup of tea sonically, are very cool looking.

My only experience with horns is with Avant Garde Duos and why I choose not to buy a pair of horn speakers. The horns seems to work well in a long room with seating not too close. The subwoofer on the other hand wants to have you seating close. There is a mis match with this combo. The bass does not flow well. Playing certain CDs like Cowboy Junkies caused the subwoofer to load up in a large room. Of course there were certain CDs which sounded really good but I play all kinds of music so I have to have all of it. I have noticed some people on Audiogon have built bass horn speakers instead of using subwoofers which might solve the problem in my mind. I have not heard any yet but I will in the future. The last problem is you can not buy these speakers but must build them yourselves. I donÂ’t do that.
Unsound, thank you for YOUR thoughtful response. I'll try to answer some of your questions:

"Wouldn't such a controlled radiation pattern reduce the size of the sweet spot and reduce the sound-stage, especially for multiple listeners?"

On the contrary, my experience with 90-degree constant-directivity waveguide-style horns indicates that they will give you a much wider than normal sweet spot when set up correctly. I use about 45 degrees of toe-in, such that the axes criss-cross in front of the listening position. Now before I go on, note that the ear localizes a sound source by two mechanisms: Arrival time and intensity. With good pattern control and this strong toe-in, for the off-centerline listener the far speaker is actually louder (greater intensity) because the listener is on-axis relative to it and well off-axis relative to the near (first-arrival) speaker. The two localization mechanisms partially offset, and you still get an enjoyable (though not perfect) soundstage even when well off to one side. The key is the smooth, fairly rapid off-axis roll-off of the near speaker. The tonal balance holds up well throughout the room.

"Wouldn't the amount of reverberant sound be greater in most indoor live venues too?"

Absolutely. In fact, I believe that two key discrepancies between live and reproduced sound are the spectral balance of the reverberant field (addressed by radiation pattern control), and the relative lack of energy in the reverberant field of most home listening rooms as compared with a live indoor performance. The latter leads us towards wide-pattern speakers, or omnis, or "poly-directional" speakers (Richard Shahinian's word). The type of poly-directional speaker I embrace is the controlled-pattern offset bipole.

"So long as the reverberant sound is not too close in time, shouldn't we be able to hear this as a reverberant sound and not as distortion?"

Yes indeed. The concept of "reverberant sound = distortion" is flawed; the ear/brain system actually uses some types of reflections to improve speech intelligibility. Part of the reasoning behind the bipolar approach I prefer is maximizing the time interval between the first-arrival sound and the onset of increased reverberant energy.

"Furthermore, couldn't this reverberant energy be controlled via room treatment and/or room correction?"

In my opinion, control should start with the sound source - the loudspeaker. It is difficult to do frequency-specific room treatment, and room correction via signal processing is microphone-position-dependent. The less spectral variation from one location to another within the room, the greater the listening area in which room correction is clearly beneficial.

"If my budget permitted, I'd guess that I'd move from cones & domes 'n boxes to top quality omnis. Perhaps the antithesis of what you've described as an advantage."

Well, a good omni inherently excels at generating a reverberant field that has the same spectral balance as the first-arrival sound, which is one of my top priorities. The only conceptual problem I have with omnis is the large distance from sidewalls required to avoid a detrimental early sidewall reflection.

"Aren't there already existing remedies for such thermal compression in many cones & domes and not really much of an issue for alternative drivers?"

My understanding is that, in general, drivers have less than 1 dB of thermal compression when used at less than 10% of their RMS rated output. Of course there may well be exceptions to this rule, and it's always the exceptions that are the most interesting.

"Am I correct in assuming that the cross-overs you describe aren't digital and therefore are probably incapable of preserving correct time and phase?"

Yes, I'm talking about passive crossovers. I do not believe that waveform preservation is a top priority, because the ear does not hear waveforms as such. At a certain very high level of performance, where more audible problems have been resolved, then waveform fidelity would be a significant issue. In my opinion, from a perceptual standpoint the tonal balance is the most important issue, but the perceived tonal balance includes the reverberant energy as well as first-arrival sound.

"It would appear to me that this ideal matching of non-horn loaded woofers to the rest of the horn loaded drivers must be rare in deed, all the horn loaded systems I've heard are blaringly bright. I have still yet to hear a horn system that's colouration's are below audibility."

Understood! In my opinion as well, it is rare. I could of course suggest a horn system or two that pays attention to these issues [rolls eyes innocently], but I must also acknowledge that some people's ears are simply more sensitive to horn-type coloration than others. If by any chance you'll be at the Rocky Mountain Audio Fest, please come by and let me know how I'm doing.

Ralph, you are correct - I left out compression driver quality. The field coil Beryllium diaphragm units John Wolff uses are magnificent. I was thinking in terms of more modest price ranges, where diaphragm resonances have to be addressed in the crossover - admittedly less than ideal, but many direct-radiator domes have comparable issues.

I think there are probably size and price floors below which a horn system is unlikely to be competitive with a direct radiator system, but above those thresholds I think good horn systems generally become increasingly competitive.
Hello Gentlemen,

Every horn system i have ever heard was heavy on the coloration side and that includes the mega buck highly rated ones. Coherency is not another strong suit due to poor integration between drivers. This effect was reduced when listening at distances of 14 ft or better.

Brings me to Now !

A friend of mine who has been heavy into planer speakers (quads, apogee, Maggies and lastly Yankee ribbon)
has obtained a huge custom horn speaker and it's associated amplifiers and x-overs , swears it's the cats meow. Pitched out his Yankee ribbon for it .. we will see !!!!

regards,
Duke, thanks again! Interesting how much we agree! Despite expectations to the contrary I too am surprised at the sound-stage capabilities of horns. I would consider this a strength of horns. I think it important to remember that room correction can be programmed for different listening positions. IME, those speakers that can preserve waveform integrity are the most enjoyable. As you wisely pointed out, we all have have our own prioritized sensitivities to different aspects of sound reproduction. I suspect that for many this aspect might not be as important. I believe you are correct, due to market considerations, R&D capital, manufacturing, shipping and handling costs, horns will have a difficult time competing in the value oriented market segment.
Unfortunately I won't be attending RMAF, my loss, it would be a pleasure to meet you face to face.
" The only conceptual problem I have with omnis is the large distance from sidewalls required to avoid a detrimental early sidewall reflection."

I've found the OHM Walsh pseudo-omni's actually work surprisingly well only a foot or two out from the side wall. That is how I have them set up currently (two pair in two different rooms).

I believe they are physically damped in the wall facing directions inside the cans specifically to enable them to be placed closer to walls than speakers with a true omni radiation pattern.
Has anyone ever listened to the Usher D-2 speakers;if so what were you impressions?
the word Phase describes a relationship it can be applied to anything really

Weseixas, Phase and polarity have very definite meanings in electronics. Just because phase has different meanings in different contexts does not mean you can use it however you want in a scientific discipline like electronics and be correct. In electronics phase has a single meaning. To say things are in phase means they happen at the same time. Out of phase means the time relationship between two signals has changed. One is occurring later in time with respect to the other. A polarity inversion means what was negative is now positive and vice versa.

When you put an audio signal through a crossover there is a phase shift at the crossover point. Some frequencies are shifted in time. No polarity change of anything. Phase dispersive as Almarg described it.

Like I said before, even though it is very common to call a polarity inversion at a speaker out of phase this is technically incorrect. There has been no timing change, we have only inverted the polarity. It is common because for a single frequency a polarity inversion and out of phase 180 degrees gets the same result (see below) but just because it is common usage does not mean it is scientifically correct. We're also not dealing with a single frequency in audio.

We say that the sun rises in the east and moves across the sky. Is this scientifically correct even though everyone says it. No, the earth rotates, the earth is moving, not the sun.

At the end of the day does it really make any difference if we say speakers are out of phase? In that context no, since everyone does it so we all know they mean the leads were reversed. The problem arises if you try to expand your knowledge of electronics and continue to confuse the two terms.

Please see the link below which says exactly what I just said. Notice the author points out that polarity switches on audio equipment are sometimes incorrectly labeled phase switches. This is exactly the same error committed when we describe switching speaker leads as out of phase.

Almarg said, "A polarity inversion is the same thing as a 180 degree non-dispersive phase shift."

It may appear that way on a scope for a single frequency but if you have a complex waveform consisting of more than one frequency you get different results. Two scenarios

(1) Take 2 signals of equal amplitude and the same frequency that are in phase...

...polarity invert one and sum the result you get complete cancellation.

...phase shift one signal by 180 degrees and sum the result you get complete cancellation.

Same result but for a different reason.

(2) Take 2 equal signals consisting of a mix of 20 hertz and 100 Hz all the same amplitude in phase....

.... polarity invert one and sum the result you get complete cancellation.

.... phase shift one signal by 180 degrees...well... here is where you run into a problem. You can't phase shift them both by 180 degrees because the periods are different. a 180 degree shift of 20 Hz is 25 milliseconds and a 180 degree shift for 100 Hz is 5 milliseconds. You can't phase shift them both by 180 degrees.

Conclusion... phase shift and polarity inversion are always 2 different things even though under special circumstances you get the same result. Sorry I got a bit long winded. Phase/polarity confusion is a pet peeve of mine.

http://www.musiciansfriend.com/document?doc_id=91427

.
Herman: Take 2 equal signals consisting of a mix of 20 hertz and 100 Hz all the same amplitude in phase....

.... polarity invert one and sum the result you get complete cancellation.

.... phase shift one signal by 180 degrees...well... here is where you run into a problem. You can't phase shift them both by 180 degrees because the periods are different. a 180 degree shift of 20 Hz is 25 milliseconds and a 180 degree shift for 100 Hz is 5 milliseconds. You can't phase shift them both by 180 degrees.
You can shift both by 180 degrees if you implement the phase shift via non-dispersive means, such as by inverting polarity! :)

I am in agreement with what you have said about how the terms "phase" and "polarity" are best used, and should be used. My point was simply that it is understandable that the term "phase" is commonly used in a loose manner.

Best regards,
-- Al
I disagree with Duke, cant always agree ;) While complex steep slope designs do have there place. If driver alignments correct and transducers horns etc are a match in other aspects. Than a low parts count simple network can have a sonic advantage[subjective since many times they measure worse]. If mating horns to standard woofer than Dukes correct. Pretty sure Old Doc Edgar would agree with me on that thought I just read a post on audioasylum where he mentioned such and Ive experimented for over 14 years with this. And Duke you would be surprised at the short listening distance Ive achieved great integration at with massive horns. Hybrid horn designs have been used in such a way in studios for decades does surprise me that many still stand by the large distance for horns since this isn't so unless loudspeaker design calls for this distance to integrate. Much easier cheaper to just say sit 10-15ft away then to attend to why this is so and optimize design. Horns can and have and continue to be designed and used for near field or monitoring use. Small rooms have and continue to be used by Japanese horn types. I could and did use my Altec A7s at 6ft distance after horns where adjusted at full angle. Worked very well. I listen to a massive 4 way front horn in my office as I type this I'm only 7ft from them. This is where I converged them to sound best. And its not shouting honking colored, trebles world class,bass pressures are present even at low levels with out bloat and full of bass detail lost to conventional designs. This isn't rocket science if some yahoo research designer in WI can pull it off. I'm sure it can be done by others. But I know WAF, large profits, hard to sell loudspeakers or other items that are not similar to others in design and appearance, this gets in the way of proper design and end performance and can handy cap most consumer products,the more mass-market the more similar,the more compromised. This is well known to any product designers and affects audio design as much as anything else.
I suppose if one wasn't interested in waveform integrity, then driver integration would be less of an issue.
phase shift via non-dispersive polarity inversion

I'm going to remember that so I can completely confuse somebody the next time this topic comes up :>)
Johnk, you're more than welcome to disagree with me. If we always agreed, one of us would be redundant!

In my experience (which is of course limited), it simply isn't feasible to use a minimalist high-pass filter topology with a constant-directivity horn because of the equalization requirement imposed by such horns. A tractrix is not a constant-directivity horn so a minimalist crossover is more likely to be feasible with it, but even then it probably calls for just the right compression driver.

To get more specific regarding driver integration with horn speakers, in my experience problems can arise when you have a high crossover (3 kHz or higher) between midhorn and tweethorn, and the midhorn is large enough that there's a significant distance between the throats of the two horns. The ear's ability to judge the height of a sound source is pretty good at short wavelengths, but poor at long wavelengths. So driver vertical integration is a function of not only vertical separation, but also the crossover frequency (and maybe crossover slope, but I'm not sure about that). In many cases a two-way horn system has a definite advantage here.

Unsound, regarding waveform fidelity, that goes to the ever-present issue of juggling tradeoffs, and my understanding of human auditory perception places other things higher in priority. Our nerves simply cannot fire fast enough to trace out a waveform, so the ear de-constructs the incoming sound based on energy distrubutions rather than waveforms. On the other hand, the ear can readily detect a broad hump in frequency response even if the height of the hump is only 1/2 decibel. So I prefer to juggle tradeoffs in favor of what I believe to matter most, namely frequency response, with particular emphasis on the off-axis frequency response because that's where the most opportunity for improvement exists (in my opinion, anyway). Now I will readily admit that the ideal would be waveform fidelity without tradeoffs in the frequency response domain, in which case the tradeoffs shift into the monetary domain.

In his landmark book "Sound Reproduction", Floyd Toole lists five measurements that have been experimentally shown to correlate well with subjective preference. Four of the five have to do with off-axis frequency response, and the fifth is the on-axis frequency response.
Duke, as I have said before, it would appear to me that some people seem to be more sensitive to wave form integrity than others. Of course those people who might not be as sensitive to wave form integrity, might be more sensitive to other aspects of sound reproduction. Though I don't have any hard statistical research to support this, the market seems to bear it out. There are many successful speaker manufactures that don't prioritize wave form integrity, and very few that do. The few that do, seem to garner consistent positive reviews, a loyal following, and enough sales to make them most successful in this highly competitive industry.
I use my horns in a two way application with a light, fast 15 inch Italian woofer. The crossover is set at 400 Hz. right now with 24 db LR slopes in both directions. I cut the woofer off at 33 Hz. and let the horn reach for the stars. My compression driver has heat sinks and is designed to play up to about 40 db louder than what I use it for.
I have a conical wooden horn made of solid cherry wood that does not seem to color anything. I'm not sure about the validity of these few comments about disadvantages in horn use but none of it seems to apply to my set up. I've listened carefully over the last few days fo signs of coloration, phase problems, compression, etc. and no symptoms are apparent to me.
Bill Woods, who designed my horns and sold them to me along with aluminum throat adaptor and B&C driver, says that these represent the best midrange he can provide and that he has tested and measured them against QUAD, Manger and Heil, which he says are the best other mid range producers. To be honest, I don't remember if he also mentioned Walsh. We haven't talked in a while.
In any case, I am not a technician and I am not one who believes I possess superior listening skills. What I can say is that I am unable to hear any lag between my woofer and my horn, and that is a tone and body to musical instruments (timbre, I guess) which I never heard equaled by any other speaker.
Perhaps I'm the one who is guilty of lumping everything together. I don't get out much and I haven't heard any other horns in years. Maybe mine are not so representative of the breed as I assumed. Nonetheless, my horns do represent what is possible and I think that a larger company could produce this caliber of work at or below Bill's prices if they could justify the research and tooling. Bill has probably already provided much of the former and the latter can be outsourced reasonably, perhaps even domestically.
Duke I agree. That to large a midhorn to low a crossover point can cause problems. Why I'm now using a oval tractrix horn this allows proper integration of drivers the oval tractrix horns has solved a few problem of round tractrix maybe give one a listen not to costly. I crossover tweeter to midhorn about 6khz midhorn to midbass about 1khz. This way I can physically time align drivers in vertical array. I also design horns so tweeter midrange can be adjust in angle so you can converge at very close listening distances if you want. Its a pain to design this way everything gets large fast. Cabinets get complicated. Crossover parts horn comps etc all need to be matched with much thought. But end results more than worth the effort.
Unsound, what do you mean by 'waveform integrity'? Is this in the circuit of the speaker or is this the output, etc and how does this relate to phase angle, if it does?

I'm pretty sure that Duke is trying to get the best fidelity out of his speakers and I have not seen that phrase used before, so I want to be clear about what you mean by it. TIA
Atmasphere, time and phase coherence, or as Duke refers to: "waveform fidelity".
Well I can't be the judge of that- I have no idea what the waveform looks like once its in the air. But compared to a pile of speakers that are supposed to be pretty good at that sort of thing I don't find good horns to be lacking.

I find bad horns to suck and not under consideration for HiFi. I don't blame you for not liking horns. I think I mentioned before that they had to win me over, and to this day when I see horns I'm not familiar with I tend to be skeptical.

IOW, Like everything else in high end, its all in the execution.
Atmasphere, until recently I didn't think that horns could possibly be capable of waveform fidelity. I am very happy to read, that it is now being addressed. Still, there are other concerns that keep me from being too optimistic.
"Waveform Fidelity". Is that the name of an insurance company? A bank? Is it somebody else we have to bail out?

Or is it a meaningless term?

Damned if I know. Anyway the problem? seems to have been resolved to your satisfaction. So what other concerns keep you from being too optimistic? And what is it we should want you to be optimistic about? If horns aren't for you, that's fine. I certainly don't want you to feel any pressure to conform. If you're happy where you are, you are a rare and blessed audiophile. Most are overwhelmed by curiosity and driven to pursue some phantasmagorical absolute sound. If you have no such compulsion, don't apologize. You hold an enviable position in the audiophile hierarchy.
The question was "Why not horns?" and you have answered as completely as anyone. Perhaps I should have asked "Why Horns?" instead.
The best horn I have heard to date, which has just been solidly reiterated by me recently been listening to my Impulse H1's (Aspara Acoustics same people)for the first time in over 4 years, it has just dawned on what I have been missing for these past years whilst living and loving the US, my usual speakers Oris 150's are good speakers, but not a patch on the H1's in terms of everything with the exception of bass depth.
Having heard the Acapella's, Classic Audio T's etc, none are as musically involving as my long time departed H1's.
So when I head back to the US they will be shipped over for sure, whatever the cost. Sorry for ranting on, but in horn terms from what I have heard they are the mutts nuts, and are comparable musically (deep breath, hand on heart) with any speaker at any price that I have heard and possibly musically streets ahead of many.
Only from what I have heard and am now hearing with my ears again folks. Sheer bliss.
In my personal case its 'not horns?, why'?
Macrojack, I thought I explained what "wavefrom fidelity" was in a previous post. I'm happy horn fans are addressing it, I'm not sure that it has been resolved to my satisfaction. The very concept of a horn suggests to me a distortion creator. I'm not completely satisfied with audio reproduction as it currently exists. I just think other design considerations might hold much more promise, such as the German Physiks carbon fibre DDD.
Macrojack:

Could you name the Horn Speakers that you consider to be good sounding ?

regards,