What’s the deal with speakers with horns?

[TLS Guy]

Heaven help you if DS-21 catches you talking like that

Personally I don't have any particular subjective criticisms on the KEF UniQ array which effectively turns the midrange driver into a waveguide, though obviously YMMV. Of course, my complaints about the Klipsch setup that preceded the KEF lineup I'm now using were more to do with frequency response than resonance, so I may not be all that attuned to the problem.

A wave guide is not a horn. In the strict sense a horn is a diaphragm radiating into an compression chamber followed by a restriction (The throat). This is followed by some type of geometric expansion, usually exponential, but tractrix has a following and sometimes parabolic. I'm not aware of any parabolic horns around now but they may be. The width of the mouth determines the low frequency cut off.

There are a number of places of trouble for HF sectoral horns. Diaphragm resonances for one, and then compression chamber/throat problems, and then you have air resonances in the expansion and resonances in the material the horn is made from.

Done well they can be good, especially in large spaces. I always thought the Klipsch were the best back in the old days of the fifties and sixties. Altec and JBL were pretty similar. The Altec Voice of the Cinema defined movie sound for generations and grew out of the old huge Western Electric horns that ushered in sound and picture.

 

[Steve81]

A wave guide is not a horn.

I've heard ugly rumors to that effect, but Swerd is addressing them both in his statements. Of course I did note in the "What Is A Waveguide" paper from gedlee.com linked in the OP that the statement was made that

It should be obvious at this point that all waveguides are horns, but not all horns are waveguides.

though his definition of a horn is a bit looser.

On the other hand they are indeed horns in the sense that a horn is any conduit of varying cross section

 

[ski2xblack]

I've heard ugly rumors to that effect, but Swerd is addressing them both in his statements. Of course I did note in the "What Is A Waveguide" paper from gedlee.com linked in the OP that the statement was made that

It should be obvious at this point that all waveguides are horns, but not all horns are waveguides.

That seems bass-ackwards. Horns do control directivity, so they can all be considered waveguides in that loosely defined sense. Horns whole purpose is acoustic gain (but they all provide directivity), waveguides are primarily for pattern control (and also increase gain a bit, but that's not their raison d'etre).

 

[Swerd]

The SEOS folks already got out the plasticine:

The primary product that has emerged is the SEOS waveguide (Super Elliptical Oblate Spheroid describes the profile of the waveguide's curvature). The design objective was to provide good horizontal coverage for near constant sound anywhere in the room (controlled directivity for the audio wonks) and vertical coverage that would minimize floor and ceiling bounce, while minimizing the problems associated with traditional 'horns' (internal reflections and such)
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Will that work better than foam plugs? Hopefully Dennis will share his impressions, he's the only guy posting who has (will soon have?) experience with both, and whose input I trust.​

I understand and respect the use of the word minimize here. It usually is more realistic and honest to say that "such & such minimizes the problem" rather than saying "such & such eliminates the problem. At the same time, minimize could also imply, "we're working on better ways to further minimize the problem".

I don't think the potential advantages of horn/waveguide mounted drivers outweighs their demonstrated disadvantages. Even if "that horn sound" can be effectively eliminated, I still have enough problems with them to prefer dome, ribbon, or planar tweeters in a standard implementation.

GranteedEV used to be a proponent of the GedLees. Too bad he doesn't hang around here any more to comment.

If I recall, he bought a pair of Philharmonic 2s, which might explain his absence. He's listening to them.

Last night, I spent a few minutes with Google Image searching the phrase: horn speakers. The results were fun to look at. I also laughed, but your responses may vary.

While looking at those photos, I think I found the horn speakers that I thought sounded OK last summer at the CAF. It may have been Volti Audio Vittoras. They look familiar, but I'm not certain it was them. They cost $17,500 a pair !

 

[TLS Guy]

I've heard ugly rumors to that effect, but Swerd is addressing them both in his statements. Of course I did note in the "What Is A Waveguide" paper from gedlee.com linked in the OP that the statement was made that

I don't think an instrument maker would regard a waveguide as a horn.
The only thing a wave guide has in common with a horn is expansion and a diaphragm. It lacks a compression chamber and a throat.

I'm not convinced about restricting radiation of a domestic speaker for the mains.
I think it is useful in center channels as it restricts interference with mains. One of the problems with home HT is the proximity of mains and centers.

That is why I use a coaxial center. It produces a cone over the listening area, but does not radiate right over the mains. It also focuses the sound to a point source very near the screen.

Where I part company with Gedlee is the desirability of restricting the dispersion of a tweeter at all for two channel audio. Basically we need tweeters with better dispersion not less. A good dispersion pattern in my view is a key ingredient to a good listening experience. That is one of the ingredients that floats instruments in a convincing acoustic space and frees them from the confines of the speakers.

 

[ski2xblack]

The Volti Audio Vittorias are awesome, but that's a pretty penny for what amounts to a hot-rodded La Scala. I wonder if Greg pays Klipsch any sort of royalties for the basic design. I've heard those at RMAF, and being an old Klipsch fan gave them a good listen. They didn't seem horn-ish to me at all, very open, airy, effortless sound.

 

[TLS Guy]

That seems bass-ackwards. Horns do control directivity, so they can all be considered waveguides in that loosely defined sense. Horns whole purpose is acoustic gain (but they all provide directivity), waveguides are primarily for pattern control (and also increase gain a bit, but that's not their raison d'etre).

That's really the issue. The purpose of a wave guide is directivity control. It might raise sensitivity one or two db, but not spl. The reason, sensitivity is an on axis measurement and does not tell about total sound radiated into the room.

A horn is powerful acoustic transformer. If you don't believe me stand in front of a trumpeter!

 

[ski2xblack]

Even if "that horn sound" can be effectively eliminated, I still have enough problems with them...

Like your wife saying, "Hell no, you're not putting those huge, ugly speakers in MY house!"

 

[Swerd]

I don't think an instrument maker would regard a waveguide as a horn.
The only thing a wave guide has in common with a horn is expansion and a diaphragm. It lacks a compression chamber and a throat.

I'm not convinced about restricting radiation of a domestic speaker for the mains.
I think it is useful in center channels as it restricts interference with mains. One of the problems with home HT is the proximity of mains and centers.

That is why I use a coaxial center. It produces a cone over the listening area, but does not radiate right over the mains. It also focuses the sound to a point source very near the screen.

Where I part company with Gedlee is the desirability of restricting the dispersion of a tweeter at all for two channel audio. Basically we need tweeters with better dispersion not less. A good dispersion pattern in my view is a key ingredient to a good listening experience. That is one of the ingredients that floats instruments in a convincing acoustic space and frees them from the confines of the speakers.

I completely agree !

Thanks for taking the time to explain the differences between horn-loaded drivers and waveguide-mounted drivers. I do understand the difference, but when typing I found it much easier to type "horn" (a four letter word ) that to type "waveguide-mounted for the purpose of controlled directivity".

 

[TLS Guy]

Like your wife saying, "Hell no, you're not putting those huge, ugly speakers in MY house!"

There is a lot of workmanship in those speakers. Horns are never small and I note a high low F3 as you would expect from a horn that size. Wood is the best material to make a horn from but there is a huge amount of work to building one.

I bet what bass there is, is very good quality. My instincts tell me those speakers are probably very good speakers indeed.

In my view really accurate bass is only produced by horn and transmission loaded drivers. They will be big speakers either way.

Open baffle and sealed alignments require too much driver excursion for really nice clean bass.

The WAF factor means that very few people have ever heard a speaker with really accurate bass.

 

[ski2xblack]

Greg makes everything by hand, horns included (except maybe the tweeter, but I'm not sure about that). The workmanship is off the charts good. His speakers are flat out works of art, and they sound as good as any La Scala I've heard (as they should for the price).

 

[Steve81]

I completely agree !

I can understand the desirability of restricting the dispersion of a tweeter at the bottom of its passband to match directivity with a midrange driver at the top of its passband. I also wouldn't be surprised if some might prefer a speaker with relatively narrow overall dispersion in some spaces (acoustically live, narrow). I don't think a set of Philharmonics would be a great fit for my basement for example, though I think them to be great speakers. That said, if if you gave me your SongTowers, I wouldn't be complaining

 

[Swerd]

Greg makes everything by hand, horns included (except maybe the tweeter, but I'm not sure about that). The workmanship is off the charts good. His speakers are flat out works of art, and they sound as good as any La Scala I've heard (as they should for the price).

See, we may actually like something in common .

I identified those speakers only from the photos, so I'm not 100% sure they are what I did hear last summer.

When I heard them last summer, I was getting tired from seeing too many displays in small hotel rooms. Most of the horn (there's that four letter word again) speakers sounded so dreadful they quickly drove me out of the room. When I heard the Vittorias, my first thought was good, I can sit here a while. The speakers sounded nice, but the guy in the room (a local dealer, not the speaker builder) wanted to talk about his tube amps and custom speaker cables, and that's what eventually sent me out the door.

 

[Steve81]

I always thought the Klipsch were the best back in the old days of the fifties and sixties.

I still need to get my ears on a set of Klipschorns...Yes, I'm a poor excuse for an Audioholic, but in my defense there's not a dealer particularly close to the DC/Baltimore metroplex.

 

[ski2xblack]

When I heard the Vittorias, my first thought was good, I can sit here a while. The speakers sounded nice, but the guy in the room (a local dealer, not the speaker builder) wanted to talk about his tube amps and custom speaker cables, and that's what eventually sent me out the door.

You clearly need one of these to keep the woo peddlers in their place.

 

[panteragstk]

All I know is that I haven't heard a horn loaded speaker I liked for music. Movies were fine, but as TLS guy said that we don't hear the massive distortion of the peaks. I sure did hear it in music. I've heard some very nice waveguide speakers (HTD level 3's come to mind) and I'd have no problem owning those. The thing I notice about horns above all else is that the seem very harsh (some more than others) and that once you get off axis even a little the sound drastically changes. I'm speaking of PA speakers specifically, the Klipsch speakers I've heard aren't as bad off axis as PA speakers. I'd still love to hear a set of HSU HB-1's since they get pretty good reviews.

 

[lsiberian]

If you make a horn right it rivals any other speaker technology. JTR makes great horns now.

 

[ahblaza]

I still need to get my ears on a set of Klipschorns...Yes, I'm a poor excuse for an Audioholic, but in my defense there's not a dealer particularly close to the DC/Baltimore metroplex.

Steve, the Klipschorns were among the first pair of loudspeakers I had the privilege and pleasure to audition at a friends house, I sat in sheer disbelief and awe of what I was experiencing, I was speechless and didn't even care what music was being played, the source was a massive turntable which I was also in awe of it's appearance, I think it was 1972, I pursued the Klips sound for a long time and could never afford to replicate that day though, came fairly close. It's amazing how audio has changed from that era, for me anyway.
Cheers Jeff

 

[TLS Guy]

Steve, the Klipschorns were among the first pair of loudspeakers I had the privilege and pleasure to audition at a friends house, I sat in sheer disbelief and awe of what I was experiencing, I was speechless and didn't even care what music was being played, the source was a massive turntable which I was also in awe of it's appearance, I think it was 1972, I pursued the Klips sound for a long time and could never afford to replicate that day though, came fairly close. It's amazing how audio has changed from that era, for me anyway.
Cheers Jeff

I first hear the Klipschorns back in the fifties pre stereo era. At that time they sounded very good. I have no heard one since the late sixties at the Audio Fair at the hotel Russel.

At that time the only speakers close to tonally accurate were the Quad electrostatics, the Klipshhorns, the Lowther horn loaded full range PM6 driver, the Jordan Watts full range driver, the Radford TL and its variants and may be the top range KEFS. Top three Quad, Jordan Watts and Radfords and its spin offs. Close Lowther.

I would like to asses the Klipschorns again. They always demonstrated them with master tapes of Jazz and lighter popular music. I always had a feeling there purposely avoided strings.

 

[ski2xblack]

Steve, not sure how far from you it is, but if you find yourself down in Charlotte, NC, go visit Panacea Engineering. I believe they have Khorns, and maybe even Jubilees, set up appropriately in good rooms.