Disc horn?

[Squeak]

I've been reading about radial horns and it strikes me that if a ~quarter of a circle works like a horn, why no just let the sound expand between two discs to create a very simple completely omnidirectional horn? Two discs with a hole in the center of one of the them, where the driver fires through. If the expansion is too fast with plain discs, it would just be a matter of putting some radial vanes in between.
This contraption could be hung on the wall to use wall loading to expand the mouth, maybe even one of the discs could be replaced by the wall?
Bogus or good idea? Prior art?

[Capt Grogg]

1939 world's fair in New York had massive example using speakers below ground using globe above to form horn to radiate 360 degrees, many smaller versions have been done

[fatbattery]

yea there is a spiral horn site. They work very well. Mount them on your walls with a fe103.

[Cal Weldon]

Google Cornu.

cornu spiralhorns, wall mounted speakers, high sensitivity ,

Cornu Spiral Copy Horn

6moons audioreviews: Cornu Compact Spiral

seb:diy:audio: Cornu Spiral Copy Horn

[fatbattery]

I saw a funky horn thing today. At the museum They had two sat dishes at each end of the room. Hight on the wall. Instead of the laser they had a Peace of drain pipe about 2inches 6ft long to the floor on both ends. Kids could whisper in the pipe at one end and hear it at the other end of the room or yell for that matter. You couldn't hear it standing anywhere Else in the room. The dishes focused the sound waves to a pin point through the room.

[Pano]

It's a fun effect!

There is (or used to be) a big pair of dish reflectors at the Exploritorium in San Fransisco. So big you can sit in them. Some Metro tunnel walls do the same thing from platform to platform, the Paris Metro being a good example.

[Squeak]

The parabolic reflector thing is older than the hills, unless you are talking a real completely flat disc, then I'm intrigued.

I know about the spiral horns. What I had in mind was something even simpler and preferably loading both front and back of the driver. No spiral. just two or three discs or squares or star shapes or whatever turns out to be best, spaced close together, so horn loading will take place at the entry point of the sound.
The back loaded disc bass horn would have to be larger in diameter and be the one closest to the wall, and probably also need a disc of wool or felt to damp anything but the bass.
What I'm proposing would radically simplify horn building.

[el`Ol]

Bahnsen

[Squeak]

Originally Posted by el`Ol

Bahnsen

That's just a regular radial horn. What I'm talking about is a disc like a giant CD you hang on the wall with spacers, with the driver mounted pointing either back or front into the hole of the "CD".
And then maybe, for mid and treble loading another smaller disc on top of the first one completely covering the driver.
This would achieve horn loading and good dispersion at all frequencies, as well as being really simple to construct.

[fatbattery]

Yes parabolic like sat dish they where sat dishes cool. I would love to see a bigger one that you sat in. I am not sure squeak what you mean. If you mean the disk is horizontal well yes It should work fine. There has been tweeter made like that I think. Two disks fanning out from the center. I sure there has been omni speakers that way too. Iam not a horn expert but Iam sure all you need is a compression chamber and a increasing area or if no chamber you have a wave guide. Does your idea have a compression chamber? omni's appeal to me as all audio sources are naturally omnidirectional.