Then a faded memory began nagging me. Long ago there was an exotic speaker design that made an audacious claim: a single driver reproduced the entire 20-20,000Hz audible spectrum. It was called the Ohm Walsh speaker and resembled an upside down funnel.
There are a *lot* of speakers which claim to be full range.
The claim-to-fame of the Ohm Walsh was that it was omni-directional (interestingly, it did use a mechanical crossover).
My own Ohm Walsh F was... deteriorated by the time it came into my possession.
Two things to note:
1) there is a guy (I can perhaps find my correspondance with him) who reverse engineered replacement drivers/cones and manufactures them.
2) There are other companies making similar designs (
German Physiks - High End Technology Loudspeaker Manufactur - DDD Driver - Products)
I recall the term "wave transmission line transducer" which I suppose is self explanatory. I guess waves transmitting down the funnel excited the air and resulted in omni-directional propagation. The inventor, Mr. Lincoln Walsh, died in 1971. I never heard these speakers perform but I'd love knowing what you think about them.
The omni-directional-ness was derived from the lack of a baffle around the cone in 360 degrees horizontal.
You could, basically, mimic that property by placing an open-basked driver face down on a box with a hole in it to allow movement. (there would be other problems with doing so simple an operation, but it would be omni-directional).
