omnnidirectional synergy horn?

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Could something like this work?
 

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Could something like this work?

Probably, but keep in mind that the actual horn is short so there will be no horn loading at lower frequencies. The dispersion will probably not be as uniform as a normal synergy horn.

A possible solution would be to open the top and bottom but damp the back wave of the midranges so you get dual opposed & slightly angled cardioids, if that would work then the response should be more uniform. I give no guarantees though, just a crazy idea that popped up in my head :D
 
Thank you all for your comments. The thing is, I've come to regard some room reflections as A Good Thing. Reading Floyd Toole's book gave me a new perspective on what a loudspeaker ought to try to do, especially as regards directivity. I recently built a pair of omnidirectional speakers and they work really well for me. I think they might be even better if the mids and highs were coming from the same point, as opposed to a few inches apart as they are now.
 
Thank you all for your comments. The thing is, I've come to regard some room reflections as A Good Thing. Reading Floyd Toole's book gave me a new perspective on what a loudspeaker ought to try to do, especially as regards directivity. I recently built a pair of omnidirectional speakers and they work really well for me. I think they might be even better if the mids and highs were coming from the same point, as opposed to a few inches apart as they are now.

Remind me of the bench mark loudspeaker(s) which Floyd Toole has designed during his private career as a loudspeaker designer. Seems he had a decent one or two with Harmon? I think Floyd made his mark at the NRC testng. Best regards Moray James.
 
Slothrop,

to me it looks like a mix between this

http://www.duevel.com/test/Wundervolle/bl3dcadtop.jpg

and a synergy horn

http://penna-media.hu/danley_web/image/danley_sh50_constrution.jpg

Since the synergy horn seems mainly a conical horn - but larger flare to the mouth - your aproach in making the mouth cylinder barrel shaped seems "intuitively valid" to me.

So a couple of conical horns may be arranged to cover 360 degrees horizontally and the lower cutoff frequency should be lowered significantly by the mouths of the multiple "cells" adding in radiation resistance.

What you do IMO is basically going 360 degrees and making a cylinder barrel shaped mouth. Then any virtual "dividers" between the sectors may be "omitted".

Of course, this one is not a conical horn, but may illustrate the idea nevertheless ...
http://www.goodsoundclub.com/Site_Images/multicell.jpg

You should keep the vertical dispersion of the synergy horn, so i would expect the free air performance to be similar like a synergy horn. I am not aware how to adapt driver, compression chamber etc. to the larger flare rate, if not going the "multicellular" aproach and also using multiple drivers.

One could go for a conventional synergy design and step by step enlarge the horizontal angle to see, which influence that has and which alignments have to be made to fit your 360 degree approach using one of the known simulation programs. But i think it can be made work well ...

Of course your dispersion won't be "omnidirectional" but 360 degrees horizontal by "X"-degrees vertical, thereby "X" being somewhat frequency dependent.

Did you know this already (?) ...
http://elac.ro/elac 4pi 2 big.jpg


Also the Walsh bending wave design has a "diffuse onmi" radiation pattern not too different from your "Linaeum" approach shown above

http://www.google.de/patents/US3424873?hl=de#v=onepage&q&f=false


Kind regards
 
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How do you measure the frequency response of an omni? Same as regular? I have an omni that sounds like, and measures like poo. I am sure the low quality driver and crappy cabinet plays a part. I try to pay attention to anybody talking about omnis so I can see if they are worth playing with.
I like the curved deflector on the ones I have. Not too different from the deflector in the original post.
 

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Yes, those old Zenith's really are poo, but not because they're 'omnidirectional'. They're just cheap. An old friend of mine had that system back when we were kids, and I remember the sound. There was a fad for omnis back in the 60s/70s, along with quadrophonic sound.

My impressions from listening to my new speakers for a week or so are very positive. They make the room seem bigger. The sound seems to be coming from a wider and more enveloping source. And the sound is good from just about anywhere in the room. So I'd say if you're thinking about trying some sort of omni build, go for it. And let us know how it goes.
 
Slothrop, The multi-sided approach you have utilized with the small dia. woofers works to further enhance the omni characteristic of the speaker, out of curiousity, where did you cross to the Linaeum tweeters? Do you employ any level shading on the woofers? Or do they all run without any padding, except that to match the tweeter....


BTW, those speakers look neither quick nor dirty to me!

John
 
Slothrop, The multi-sided approach you have utilized with the small dia. woofers works to further enhance the omni characteristic of the speaker, out of curiousity, where did you cross to the Linaeum tweeters? Do you employ any level shading on the woofers? Or do they all run without any padding, except that to match the tweeter....


BTW, those speakers look neither quick nor dirty to me!

John

Thanks, John. The mid/high crossover is at 4kHz, keeping it out of the voice band. I have a sub for <120Hz or so. All the midwoofers are running at the same level.

Maybe I should give them their own thread.
 
What about coaxials as in some Danley's speakers?..

Just assemled one really quick&dirty conventional (~80º*50º) synergy (1000years bedside-table remains, 2*5" 3W paper mids w\o magnets and $100 China 3" B&C, blanket instead of mids boxes), first order :) xover. Working from ~100-150 Hz.Mids are forward about 0.2 ms.
Seem's I practically like synergy concept.. :smash:
 
What about coaxials as in some Danley's speakers?..

Just assemled one really quick&dirty conventional (~80º*50º) synergy (1000years bedside-table remains, 2*5" 3W paper mids w\o magnets and $100 China 3" B&C, blanket instead of mids boxes), first order :) xover. Working from ~100-150 Hz.Mids are forward about 0.2 ms.
Seem's I practically like synergy concept.. :smash:

For a radial horn, the pancake method is easier.

With a coax you have to figure out how to match the angle of the horn walls with the angle of the woofer cone in the coax.

I'm guessing that's why all the Danley speakers that use coaxials are molded*. The tolerances required with a coax basically dictate something made with a mold.

* there are some wooden Danley horns that use the BMS coaxial compression driver, but that's a different beast altogether.
 
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