Warning: this is a really dangerous and stupid idea. On the other hand it would provide almost infinite frequency response especially at the low end of the spectrum.

A strong magnetic field is imposed with the north pole and south pole opposing each other. Across the air gap metal plates provide a high (variable) voltage. The air is made conductive by a source of ionizing radiation. The current perpendicular to the magnetic field produces a force on the air that can be modulated to produce any frequency of sound. Since there is no speaker cone, travel is not limited.
-- brewer, May 14 2006

(?) Plasma Speakers http://www.free2cod...ew.php?f=29&p=47226
Background Info. on similar technology [csea, May 14 2006]

Propane Tweeter http://www.plasmatw...r.de/eng_plasma.htm
[loonquawl, Feb 13 2009]

Interrresting. Did you know there are propane flame tweeters?
-- BunsenHoneydew, May 14 2006


// A strong magnetic field is imposed with the north pole and south pole opposing each other. // What choice is there?

Could you expand on the principle? There is a magnetic field (static?) and an electric field (perpendicular and variable?) and the air is conductive (to provide an arc?) - So what you want to happen is ions in the air being accelerated in the electric field, and influenced by the magnetic field? Where do they go afterwards? what produces the sound?
-- loonquawl, Feb 13 2009


//what produces the sound?//
presumably that crackly "thwuum-thwuum" you get from a Jacob's ladder.
-- coprocephalous, Feb 13 2009


// Could you expand on the principle? […] //

It's a magnetoaerodynamic pump used as a rotary woofer.
-- notexactly, Apr 23 2019



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