How come Horn + woofer designs are not more popular?

I think JBL M2 have too low sensitivity 92dB  for horn + 15" woofer speakers.
This fact kills they advantages over box speakers.
Yes, they should have better high and low frequencies extension compared to typical horn speakers, 
BUT
They will never sound as dynamic and alive as 97-100dB horn speakers and you can't use them with SET amplifiers.
I listen mostly jazz and classical music, and for this kind of music low mass old 15" woofers like where used in: old Altec, JBL L200, Tannoy Silver, Red suit better. 
New heavy 15" woofers more suit for rock and pop music but they don't breathing and sound more simplified on midrange. 

Speaking purely subjectively, for me speaker brands highlighted different things.  As a musician, I prefer to evaluate audio with music that doesn't rely on amplification for its realization, hence acoustic instruments.  Since I was a young teen, I've loved the way piano sounds on JBLs (I've had a Steinway grand almost since then).  I was blown away when I heard Wagner on a pair of Bozak Concert Grands.  Strings always had an unmatched warmth for me on KLH.

I've owned and loved JBLs since a teenager (over 50 years ago!), acquiring a bass reflex system with D130s alone at first, adding "potato masher" horns around 1970.  I still have them, and recently hooked in a pair of O75s.  In the early 1990s, I lucked upon a Paragon and vintage McIntosh MC240 & MC275 amps.  At first, I thought the sound impressive, but a bit harsh with weak bass.  The harshness increased as one moved closer to the horns, of course.  Subsequently, I learned that the previous owner listened at less than a moderate level (he had a cheap L Pad attached to it for convenient volume adjustment!)  I added a graphic equalizer and used it for years until I noticed that the (stiff?) 150C woofers had blossomed.  I took the equalizer offline and added a pair of JBL 2405s in parallel with the O75s.

My friends, mostly professional musicians, never failed to be impressed.  However, for me, there was yet a ways to go.  Five years ago I installed a McIntosh MEN220, "Room Perfect" component—bi-amped with an MC2105 for the low end and the MC275 for the horns and tweeters.  After running the room correction algorithm, I found that a great majority of what I had perceived as shortcomings were essentially gone.  There's nothing like live music, but this system continues to give me a thrill.

Horns can be the last loudspeaker you would ever need to buy good ones are not obsoleted as quickly or at all like nearly all conventional dynamics and estats.  They hold up well with time unlike the many others and can be easily repaired or upgraded. Horn based systems are great at producing a near real sound that the other types struggle to produce. But they are large take skill and knowledge to set up and are a bit harder to source. The best in horns is fully horn loading and most consider this just a bit to much to pull off. So many of those who claim to have heard a horn system most likely only heard hybrids not full horn loading. 

My Heresy IIIs were extremely easy to set up...you take them out of the box, put them in front of you, attach the wires...

Look how large a K Horn midrange horn has to be just to get down to 500 Hz were it crosses to a 15 inch woofer. This is one area were that ESLs have a major advantage over both horns and dynamic speakers. You can easily design a speaker that is One Way all the way down to 100 Hz as long as you can live with the size.

@mijostyn   The Classic Audio Loudspeakers model T-1 employs a machined horn that is crossed over at 250Hz. This is an easy speaker to google images. The trick to getting horns to go this low (500Hz is easy) is to use a modern surround like Kapton for the compression driver. This was solves one of the more serious issues facing old school drivers- breakups resulting from inability to deal with excursion could make older drivers somewhat painful and screechy. OTOH, crossing over a 15" woofer at only 500Hz is pretty easy- most of them can go considerably higher than that without breakups.


Admittedly the T-1 is a speaker that has been too large for my listening rooms but CAL also makes a version of the same idea that is taller rather than wider (the T-3) and that does fit. One advantage horns can have is that they can be a bit easier to place. My speakers are only 3" from the wall behind them yet they play soundstage width and depth with ease.


IMO/IME a lot of people that are down on horns really haven't been paying attention to how far horns have progressed since computer power has become so ubiquitous. Duke's loudspeakers (Audiokinesis) are also a good example of that and Duke is also a master at crossover designs that really blend seamlessly. Understanding how the horn is to be used (a PA horn is often not ideal in the home for example) can eliminate entirely that 'horn sound' to which so many audiophiles object.

Audiokinesis, I would like you to tell me how you would make a two way hybrid horn speaker.
Otherwise I could not agree more. The business about woofer "speed" is unfounded. The only issue with the larger woofers is pistonic control thus the use of stiffer pleated surrounds. The free air resonance of these drivers actually tends to be higher in spite of their size. Theoretically with a larger woofer the distortion should be lower as it is more likely to be operating in it's suspension's linear zone.
I do think the directivity of horns is an advantage. But I think you minimize primary reflections from the floor and ceiling. I am not learned in horn design at all but I believe you can make a horn more directional vertically than horizontally which would improve things. The reason I am so fond of dipole vertical arrays is that you only have one primary reflection to worry about, the one behind the speaker which is easy to deal with aside from the way they project power. As you say late reflections are not a problem as long as your listening position is well into the room. Having your seat right up against the rear wall is....not a good idea. Then there is the issue of room size. Small rooms are never going to sound as good as large rooms. All the late reflections come too early confusing the sound stage.
IMHO rooms smaller than 15 X 25 should not be used for an ultimate system. You can scale a system down to a 10 X 18 room but that is not going to be ideal as the sound stage is going to have a less than realistic size. 

@johnk --

... The best in horns is fully horn loading and most consider this just a bit to much to pull off. So many of those who claim to have heard a horn system most likely only heard hybrids not full horn loading.

Indeed, John. Horn-loading all the way down into the upper, central and sub bass potentially lifts the presentation into another realm with better coherency, dynamics, ease, refinement and visceral impact. Certainly the importance of horn-loading the lower midrange and upper bass, where most would choose a direct radiating solution, has significant impact as well being that the predominant "founding imprinting" and energy resides here, and helps in tying the overall presentation together. A properly integrated all-horn setup delivers a sphere-like, more realistically scaled/sized and uninhibited presence, and horn-loaded central- and sub-bass simply blows away most any direct radiating solution both in regard to dynamics, "airiness," ease, refinement and sheer force. Headroom is one of the key words here, but it’s not about loud per se; it’s about enveloping, effortless and uninhibited presence at any desired volume, an aspect you cannot write realism out of. Most haven’t heard horn bass though, so most don’t know.

@atmasphere --

IMO/IME a lot of people that are down on horns really haven’t been paying attention to how far horns have progressed since computer power has become so ubiquitous. Duke’s loudspeakers (Audiokinesis) are also a good example of that and Duke is also a master at crossover designs that really blend seamlessly. Understanding how the horn is to be used (a PA horn is often not ideal in the home for example) can eliminate entirely that ’horn sound’ to which so many audiophiles object.

I agree, with the caveat that horn sound qua horn sound, even rid of overt colorations by virtue typically, but not only, of more newly developed iterations (with the understanding that direct radiators, planars, electrostatics etc. have their share of colorations/limitations too in a variety of forms), by their very nature have a higher degree of directivity (more direct sound compared to reflected ditto), a more pronounced sense of presence, typically bigger image size, better transient abilities, dynamics and so on, the latter of which has some believe this aspect is even exaggerated. All-horns rid of overt colorations and issues in relation to integration still don’t fall in line with those who prefer a more laid back, less direct presentation with muted dynamics. I would believe though that a well integrated and developed quality horn setup - preferably, by its proper definition, an all-horn setup - would impress more audiophiles than it wouldn’t.

Dear all, sorry for a long post here - but here is some experience, using a horn system with OTL amps - Audiokinesis Dream Maker and LCS speakers and Atma-sphere MA-1 amps.

I have no commercial connection whatever with the manufacturers mentioned here, I am just a listener who has paid for what I’ve got. It has been a long time, a long trial period, adjusting a system to a quite large 27 x 20 feet living / listening room. The system in our room plays best from the 20 feet short side, whatever the speakers or amps.

Our former system was a more "pinpoint" solid state system with a big Krell FPB600 driving Dynaudio Consequence speakers. We selected the Consequence speakers, their flagship at the time, after some speaker testing with the Krell amp in 2002, involving B&W Nautilus, Proac, and others. However it was only later that we realized that the Consequence speakers were so power-demanding that they needed two Krell amps. I had invested in Krell amps upwards in capacity over ten years, but I now became sceptical. The FPB600 sounded "shouty" especially on mid-level volume. Probably mostly due to the non-optimal match with the speakers. The Krell amp only kicked into full state A solid-state at a very high level. That’s when my neighbour knocked on the door!

In other words, the system was great, except for needing a high volume level, and even then, the Consequence speakers were designed for an even more massive amp than the Krell FPB600.

We lived with this, for some years, getting a better phono preamp (Aesthetix Io) and, and eventually a tube preamp (Einstein The tube). But it wasn’t quite what I wanted. I even got a Velodyne DD18 sub, but the integration was so-so.

Twelve years ago I invested in an OTL amp in my desktop system (Auditailor Jade). I felt so much sonic comfort that I decided to change the amp in my main rig also. I invested in Atma-sphere MA-1 monoblocs, and eventually upgraded them into v 3.2.

I also followed Atma-sphere’s advice regarding speakers. Very happy that I did.If you don’t get speakers that are specifically good for tube and OTL amplification - you are wasting your money. Believe me. I tested several 8 ohm designs, Yes these speakers could do the job (somewhat better with zero transformers - that however contradict the principle of OTL and gave a bit of veil). But to sound really excellent, OTLs like MA1 needs higher ohm and high sensitivity speakers.

So what is my verdict, now?
Does my system sound "shouty"? No. Actually less so, than my former Krell / Dynaudio system. Is it "pinpoint"? Maybe a bit less. Depends on the definition. Not sure. Much depends on the speaker positioning. Audiokinesis advices that their speakers cross a bit in front of the listener. I find that the Dream Makers sound best, a bit more conventionally toed-in, crossing a bit behind the listener. The LCS effect speakers do make an improvement, but they need to be tuned down in volume, not attract attention to themselves. Besides more "air" and "room" with the effect speakers connected, the benefit includes a more smooth bass response. I seldom miss my Velodyne DD18, even if it went a bit further down in frequency.

Mijostyn wrote:  "Audiokinesis, I would like you to tell me how you would make a two way hybrid horn speaker."

I'm leaving for an audio show in a few hours and don't have time to write you a decent reply right now, but will attempt to do so in about a week.

Duke

@mijosyn 

Audiokinesis, I would like you to tell me how you would make a two way hybrid horn speaker.

Not meaning to be glib, but the short answer is 'very well'. Duke's Dreammaker loudspeaker is a 2-way employing a woofer and wave-guide style horn, with a rear-firing complement as well. Its easy to drive and wide bandwidth; very neutral and musical. 

I'm not being facetious guys. I am trying to learn here. Way back I had Heresys and I loved them. In 1970 we did not have much for power. With a Dynaco Stereo 120 these things would rock. No deep bass but then nobody knew about sub woofers. They were three way. So let's assume we are using a 12" woofer infinite baffle and cross at 1000 Hz to a horn, what does it take to make a horn go from 1 to 20K with reasonably even dispersion and not sound like a goose honking. Duke's Speaker has multiple other drivers including three tweeters firing out back along with whatever is in the LCS box. It is anything but a two way hybrid horn speaker which to me means one horn and one woofer. I have never heard Duke's speaker and I am making absolutely no comment on their performance. So please Audiokinesis if there is a way to do this I would love to know. Like I said before my knowledge of horn technology is limited. Hear from you when you get back. 
Another issue that bothers me a little is the assumption that horns are more dynamic than other speakers. Horns are more efficient than most other speakers for sure but any speaker can be just as dynamic given enough power and power handling capacity. Horn speakers may have an absolute higher volume level at a given distance but very few of us listen at those levels. Our ears do have a pain threshold. In the end horn speakers are point source radiators and I personally do not think they present the music in as realistic a fashion as an ESL or Planar linear array. Maybe someone will build a horn version of Bob Carver's Ultimate line source. Think what that would look like:)

Maybe look like this:


https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcQqpiyaSILlE-Pn08uX5QCVqzd5e0O5a52YRr5xAxUTXZ29...

Wow, that should scare the hell out of your wife.

@mijostyn --

Another issue that bothers me a little is the assumption that horns are more dynamic than other speakers. Horns are more efficient than most other speakers for sure but any speaker can be just as dynamic given enough power and power handling capacity.

That’s just the problem; with less efficient speakers and a sensitivity typically below 90dB’s "enough power" for proper dynamic envelope will largely be converted into heat in the voice coils (and crossover components as well). Depending on one’s size of listening space, distance to the speakers, room-acoustic characteristics etc. the power capacity needed for reasonbly uninhibited, realistic dynamics can very easily reach hundreds of watts, with thermal issues and power compression looming closely or already in full display eating away precious dB’s.

Imagine a not uncommon sensitivity of a direct radiator speaker sitting in the 84-87dB range compared to an all-horn speaker of 104-107dB’s sensitivity (or a horn hybrid sitting between 94-97dB’s, which will also make a big difference with ~1/10 the wattage requirement). The latter will need ~1/100 of the power - probably even less when we factor in power compression - to generate the same SPL as the former, and so full dynamic capacity with an all-horn setup, in a domestic environment, can actually be achieved close to realistically without thermal issues, and headroom to spare. And this, headroom, is hugely important. It’s not only about having "enough;" it’s about having sufficient headroom, even through blasting crescendos, for the speakers and amp(s) to more or less ease along so that the actual perceived sonics feel "at ease."

In the search for dynamic prowess it's also worthwhile to look at the possible sonic implications that follow with the  process of acoustical impedance transformation. A horn couples the cone movement to the air gradually and more efficiently than a direct radiator, and this impedance coupling "latches" the cone movements to the air in such a way, to my ears, that transient snap and dynamic feel (and presence) is heightened. The cones in all-horns also move much less for the same SPL, and therefore inertia is greatly reduced for even better transient abilities.

Headroom, again, is very important. I’d even go so far to state that for headroom to be sufficient, all-horn or horn hybrid setups with ~+97dB sensitivity is a minimum requirement if we’re to attain fairly realistic and effortless dynamics. A radical thought to some, I’m sure..

Horn speakers may have an absolute higher volume level at a given distance but very few of us listen at those levels. Our ears do have a pain threshold.

Most compressed music has limited dynamic range, and thus quite easily feels rather loud. Music not severely compressed will retain dynamics more realistically, and the average volume will feel lower. It’s not as much about loudness per se as it is ease and the overall feel of the music, and a setup sonically at ease will sound subjectively lower (but we should still be aware of SPL’s to spare our ears). When I listen to a proper all-horn setup the uninhibited presence and size/scale is addictive, and makes most direct radiators I’ve heard seem rather tame/less alive and malnourished by comparison. Many mayn’t expect it, but quality implemented horns have a warmth and vibrancy and easy-on-the-ears imprinting that’s anything but strident, shouty, nasal, hard or what have you.

I'm not actually in your discord, but who else in your group has 4367?

Phusis, all that is nice but relative to what? We are not trying to blow up the Empire State Building. If you like pea watt amplifiers then you need all the efficiency you can get but in real life you can get all the volume and dynamics you need with dynamic drivers and good powerful amps. I am a linear array ESL fan and I guarantee you will never get as realistic a presentation out of a horn system all that rubbish aside.

Mike 

Not everyone has enough lines in their house to energize all those panels. Even a pair of Stax ESL 4X are going to draw 4000w idle.

I’m not being facetious guys. I am trying to learn here. Way back I had Heresys and I loved them. In 1970 we did not have much for power. With a Dynaco Stereo 120 these things would rock. No deep bass but then nobody knew about sub woofers. They were three way. So let’s assume we are using a 12" woofer infinite baffle and cross at 1000 Hz to a horn, what does it take to make a horn go from 1 to 20K with reasonably even dispersion and not sound like a goose honking. Duke’s Speaker has multiple other drivers including three tweeters firing out back along with whatever is in the LCS box. It is anything but a two way hybrid horn speaker which to me means one horn and one woofer. I have never heard Duke’s speaker and I am making absolutely no comment on their performance.

@mijostyn Thermal distortion caused by instantaneous voice coil heating is why horns tend to be more dynamic than regular box speakers- horns are really the only way to keep up with ESLs in this regard.

Regarding your question above- cross the horn at 500Hz and you have no worries with the woofer doing everything below that. Duke’s speakers are usually two way designs; the other drivers you see in the online photos are the late ceiling splash drivers. So concentrating only on the two-way aspect, Duke has often used a wave guide horn that looks a bit like a trumpet mouth giving even forward dispersion in both vertical and horizontal planes. I don’t know where Duke crosses his speakers over but I do know he spends most of his time sorting out the crossover to deal with the peculiarities of the drivers themselves- this is the thing at which he excels.


At any rate, modern horns are pretty well sorted and have been for at least the last 20 years. The real trick lately has been getting the driver to interface properly to the horn- so throat designs have improved simply through computer optimization, and after only about 60 years driver manufacturers sorted out that if they had a better surround than just the material of the diaphragm itself, that they could get wider bandwidth and less breakups. Its these latter two things that have caused modern horns to be as smooth as any other loudspeaker technology.

@mijostyn --

Phusis, all that is nice but relative to what? We are not trying to blow up the Empire State Building.

I believe you missed my point. It’s not about loudness per se, but for loud to be effortlessly loud when needed, emulating to a certain degree a live performance here, and for the overall listening experience at levels relatively "normal" to gain from sufficient headroom as well; headroom defined as a requirement not only necessary, but "sufficient" re-defined as that which raises the bar to an at least ~15dB headroom requirement - not easily attainable when you need, say, 105dB’s peak with low to moderately sensitive speakers. This level of headroom may seem crazy to many, unnecessary indeed, and plant associations relating to structurally unsound, ludicrous-level (nice Tesla-coined term) playback that you’re clearly getting at, but I hope you know by now what I’m trying to say.

If you like pea watt amplifiers then you need all the efficiency you can get but in real life you can get all the volume and dynamics you need with dynamic drivers and good powerful amps.

You could certainly get along much more easily or fittingly with "pea watt" (2-5 watts, I take it) amps such as SET’s with very high sensitivity speakers, a rather obvious pairing, but going by my own usage I’m not necessarily an advocate of such with a 30 watts pure Class-A solid state amp for 105dB sensitivity main speakers. Very low powered amps do have their merits for sure. I can tell you this though: I’d much rather have 105dB sensitivity speakers with a real-life 30 watts Class-A amp than an 85dB ditto paired to a 3 kilowatts amp..

I am a linear array ESL fan and I guarantee you will never get as realistic a presentation out of a horn system all that rubbish aside.

"Fan" being the operative word. Granted, I just like horns.

That is why Howard Johnson made 28 flavors. But, too bad we could not hear each other's systems.

Hi folks I supplied some long term user information regarding horns. What about some others, not just opinions - ?

The Audiokinesis Jazz Modules were are good example of a well done two way horn. I owned one for several years before going over to ESLs. Given the chance I'd own them again but they are no longer made due to the TAD 1102 drivers being unobtanium. I was just in Long Beach for the audio show and Duke displayed his new Gina satellite speakers (using custom Emminence drivers made for him) which were demoed with his Swarm. A very nice set up using the round wave guide the Jazz Modules featured in a two way stand mount design.

Interesting, Clio09. I feel lucky to own a pair of Audiokinesis Dream Makers, that probably sound even better than the Jazz Modules (have not compared). My respect for them, and for Duke's philosophy and design, has grown over the years.

I think a main reason why (good) horn speakers are not more popular is that most people have not heard them. I mean not heard them over a longer period of time, with good tube amps. When I switched from solid state to tube (OTL), at first it sounded dull, blurred, anemic. It took time to get used to the new sound. Most people haven't had that chance.  

@o_holter, I have heard both versions of the Dream Makers, the original with TAD drivers and the newer series. Yes, they are better than the Jazz Modules, but they are also much bigger and more expensive (although with anything Duke makes still a great value). I heard them with the LCS add on as well. While the LCS does everything it is intended to do, it wasn't my cup of tea. The Dream Makers on a stand alone basis were much more to my liking.

BTW - I have owned Atma-Sphere amps for quite some time and as you know they are a great match with Duke's speakers.

@mijostyn --

That is why Howard Johnson made 28 flavors. But, too bad we could not hear each other’s systems.

Indeed, re: flavors. And, most definitely - it would be very enlightening listening to each others setups, and find out what words (and sitting behind the screen arguing) can’t quite get at. I have my preferences, sure, and overall I find a well-implemented all-horn system to provide something special. On the other hand it’s interesting listening to other peoples systems and get to know where they’re coming from, and what motivates their journey. Mostly I find there’s something worthwhile to appreciate here and sometimes even to be inspired by.

Occasionally I have a tendency to downplay the qualities of my own setup, even though I cherish it on a daily basis, because I listen to it so often and get used to its traits like coherency and dynamics; then, when I listen to others systems my initial reaction can be one of being in favor of this new sound just by virtue of it being new and bringing something different to the table, but after a while the pendulum swings back and stabilizes for a more level-headed approach.

A friend of mine got a fully active setup with waveguide-equipped S.P. Tech Revelation main speakers that are augmented by a pair of Electro Voice 880DM cinema subs (2x18" per sub), and the sonic totality of this system ranks among the very best I’ve ever heard. The tonality, smoothness, scale and overall authenticity is simply breathtaking, and listening to organ music from this setup actually lends you the impression of something reminiscent of a live performance, which is saying a lot. Very few systems I’ve heard are able to even remotely give the sensation of authenticity with organ music.

On the hand listening to my own setup - which still lacks a bit of fine tuning the sub-integration and room acoustics even further - feels more vibrant, "ignited," liquid and alive (also a lower volumes), and I find overall coherency better here. I’d wager the transition from 2x8" units from the S.P. Tech mains to 2x18" from the EV subs reveals itself as less energy-coherent compared to going from a horn-loaded 15" in my mains to a tapped horn-loaded 15" in my subs. Then again my setup can’t quite equal the image height and overall response-smoothness found in my friend’s system. Interesting observation: even though my friend’s system uses 2-3 kilowatts over his mains, fully active, the 30 Class-A watts over my passively-driven all-horn mains seem to deliver more uninhibited dynamics (no, it's not that I'm lured into believing what's actually distortion acts as dynamics here - re: @atmasphere).

Clio09 - the LCS effect speakers are a bit of plus and minus in my system, but tuned right (and turned quite low) they are mainly a plus. Helps fill the room, smoother bass, some more dimensionality. But I agree, the Dream Makers alone are very good indeed. My pair, made in 2013, came with Celestion CDX1-1445 compression drivers and Acoustic Elegance TD10X woofers. I've later changed to  PRV Audio D290Py-B compression drivers.

I would guess that Dream Makers like other AK speakers sound best with beryllium tweeters, but I have not heard them. The PRVs lifted a veil compared to the Celestions, so thats why they stay put, but I may test with the Celestions, later. They had an organic quality that I liked. Duke made the x-over tuning with the Celestion / Ac elegance combination, but he also wrote that the PRVs could be worth a try. I tame them a little bit by small wool "collars" placed around the mouth of the horn.