How come Horn + woofer designs are not more popular?

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.