Large multicellular horn ?

[seti]

Instead of cluttering another thread I decided to start a new one. I've seen lots of multicell horns lately. They are basically lots of little expnential horns. What are teh advantages and disadvantages of such horns? How do they compare to todays horns? I think they look really cool but how is the performancea and sound.

[Cut-Throat]

All I can tell you was the difference between a Stock Khorn and a Modified one with this 1005B horn and 288-16K driver was simply amazing! - I first heard this set up at a Friend of mines house and the next day I went shopping for a pair of Big Horns. I'll be interested in this thread, because I really don't understand 'Horn Technology' - Except that I like what I hear !

Hear is a picture of my Modified Khorns that I have now had for 4 years.

[tigerwoodKhorns]

All I can tell you was the difference between a Stock Khorn and a Modified one with this 1005B horn and 288-16K driver was simply amazing! - I first heard this set up at a Friend of mines house and the next day I went shopping for a pair of Big Horns. I'll be interested in this thread, because I really don't understand 'Horn Technology' - Except that I like what I hear !

Hear is a picture of my Modified Khorns that I have now had for 4 years.

Do you notice any negative effects from mounting your tweeter below the midrange diver?

[Cut-Throat]

Do you notice any negative effects from mounting your tweeter below the midrange diver?

Nope.

[seti]

On the old K5 PWK mounted the tweeter right in the middle of the horn.

I am really curious about these horns.

[Blvdre]

I would imagine the cells help with dispersion, especially at higher frequencies. Just a guess, though.

[Invidiosulus]

I would imagine the cells help with dispersion, especially at higher frequencies. Just a guess, though.

That's what they are supposed to do.

Since the highs are going to beam, just make them beam all over the place( in a good way).

[Don Richard]

Advantage: More even dispersion.

Negatives: Increased lobing and comb filtering.

Multicells were an old solution to a problem now solved better with constant directivity horns.

[CaptnBob]

Yeah, what Don said. Lots of weird phasing effects. There are reasons people stopped using them for home applications, besides size.

True fact. Back in old days, a way to control dispersion with one of these things was to stuff the cells pointed in the wrong direction with towels or rags.

[Clipped and Shorn]

#290273517769

Pretty, but think I will pass for now.

-zncx

[claus ernst]

You are right, Don. These multicellular monsters create problems in home use. They were made for theaters where the listener is seated a couple ofmiles away from them. In near field home use even a 811 horn does some nasty things /comb filter and reflections... Don't move your head while listening! But in really large rooms they can do a fantastic job.

[Cut-Throat]

#290273517769

Pretty, but think I will pass for now.

-zncx

Now those look Kick-*** - I think I'm gonna have to get me a pair of his 10 cell Horns ! - a 30 day return policy makes it even easier !

[Don Richard]

You are right, Don. These multicellular monsters create problems in home use. They were made for theaters where the listener is seated a couple ofmiles away from them. In near field home use even a 811 horn does some nasty things /comb filter and reflections... Don't move your head while listening! But in really large rooms they can do a fantastic job.

There is a new take on this where vanes similar to a multicell are employed, but only in the throat area. Invented by Meyer Sound, AFAIK, it is called REM for ribbon emulation manifold, an outgrowth of line array technology applied to point source loudspeakers. By dividing the throat only into cells, HF dispersion is improved without inducing comb filtering and lobing.

[seti]

Bill Woods of acoustichorn.com posed a reply to this question on another forum. Here is the re-post:

Multicell horns are overlooked in my opinion.

They have a few advantages.

1: they have a very large source size verses frequency.
Each cell will have a specific cutoff for it's length and mouth area.

But you can make 9 cells or one cell-- all with the same cut-off
frequency. You get a very large sound source. The large source is part
of sound realism ( see Olson's book (--page 602-- "Acoustical
Engineering" from Old Colony)

2: The throat geometry is quite good due to all those cells culminating in one place. ( no pinching)

3: The directivity is the same anywhere in the coverage angle of the horn sidewalls.

4: The much touted beaming of each cell is not that noticeable if you move your head just a few inches.


The
negatives are they are very expensive to build, and they have an
exponential flare. Having said this, I think most people would find a
properly set up multicell to be very rewarding.


If you would like to see a curve of a 300Hz multicell, I will post one on my website.

http://www.acoustichorn.com/news/index.php

[Cut-Throat]

You are right, Don. These multicellular monsters create problems in home use. They were made for theaters where the listener is seated a couple ofmiles away from them. In near field home use even a 811 horn does some nasty things /comb filter and reflections... Don't move your head while listening! But in really large rooms they can do a fantastic job.

My horns are in a 23' by 28' foot room and have none of the problems that you describe.

The sound is simply lovely. I just spent 3 days at the RMAF in Denver, and I'm not upgrading....

[Coytee]

Having never seen (in person) one of the multi cellular horns, I'm just wondering...

With one driver, wouldn't each cell have a signal that is essentially aligned with each other cell?

If so, would it then be reasonable that any slight overlap of adjacent coverage area (of properly aligned signal) would be a LESSOR heinous problem than perhaps the more typical reality we find on something like a Khorn where you have non-signal aligned sources in adjacent bands?

[]

[ZAKO]

No !!!!!!

[Coytee]

No !!!!!!

hmm.. Well... good thing I'm a dummy!

From a lay point of view, I would have thought if the source was say... a floodlight then all the cells of the horn would be putting out 'essentially' the same sourced/aligned light beams. contrast that to the offset we seem to have with the misaligned signal in the Khorn (again, I'm only referring to something like the Khorn so I reserve the right to be absolutely wrong yet again! [])

Anyways... I'll fall back onto something I always heard my father say when I was a child. (when things are going very wrong for someone)

"when you have a bunch of indians (problems) coming over the hill to kill you, you need to worry about the closest one first" Paraphrased I guess, but you get the gist.

So... if we have a plate of problems (opportunities) with our system... it would seem to me to make sense to 'killing the worst offender first' before worrying about the more subtle issues would garner some better (and probably easier?) gains in sound.

Meaning... I would think aligning the signal in a pair of Khorns would yield a quicker/better benefit than worrying about what kind of wires I'm using. I would think fixing room issues would yield quicker/better benfits than swapping out two different (properly working) amps.

Once you make the speaker as perfect as you can make it....once you make the room as perfect as you can make it THEN I'd suggest you can start to look at the smaller issues and fix them as adjustments.

I would have thought that the multicell horn would merely be dispersing the same sound in each cell since each cell comes from the same point source.

I certainly may be wrong.... just sharing how my brain works. [Y]

[Don Richard]

I would have thought that the multicell horn would merely be dispersing the same sound in each cell since each cell comes from the same point source.

That was the idea behind this type horn. What you then have is a cluster of exponential horns. The highest frequencies are kept separate by the cells, and spread fairly evenly. So far so good. But each individual cell does not have a large enough mouth to exert pattern control at the low frequencies so there is interference from cell to cell.

Although the acoustic origin for each cell is the same, the acoustic centers are separated. Simply put, the acoustic origin is the driver's diaphragm, and the acoustic center is the point from where the sound emanates, which in an exponential design is at the mouth. Whenever one has the same sound coming from sources separated in space (time), lobing, combing and time smear occur.

This solution for even dispersion was the state of the art in the 1930s, but problems were noticed when these horns were used for speech reinforcement in acoustically live spaces. Intelligibility suffered, and multiple, larger horns were found to perform better when properly aligned acoustically.

[mark1101]

They still look cool though.