Wild & exotic speakers

[cravnsn]

We’re all familiar with the idea of using paper, plastic, Kevlar, carbon fiber and various metals to make the speakers we have in our respective homes. There are speakers with ribbon & Mylar drivers, and multiple drivers used to reproduce sound, but here are some wild & exotic drivers you may not even know existed, like wool speakers:



Or a full range driver made from banana plant fiber (and the elaborate enclosures they go in):





Speaking of enclosures, we all know wood makes for a good enclosure, but what of the speaker itself?:



High end warm clear sound created from the grains in the wood cone, cast aluminum frame and rubber surround.

And the wildest (IMO) doesn’t even use a driver with any mass – it uses plasma.



It is really simple. It is a modulated RF power amp with a controlled ionic discharge.
By modulating the oscillator with the audio signal the flame size changed and so the air pressure changed also. You hear the sound directly through the air without modulating a diaphragm.
So there are no moving parts, no distortion and none of the problems other tweeters have. The signal is quite low in level ( I measured 82 dB with my prototypes ) but it is the cleanest sound I ever heard. I use no horns to increase the sound pressure so you don’t have to sit in axis of the tweeter, the sound is everywhere in the air.
You need a lot of RF power to get a ionic flame so I use a tube (valve). I choose a EL519 you can also use a PL519, the PL has only a different heater voltage ( 40 Volt / 300 mA ). The RF power is easily modulated on G2 of the valve. I use a transistor, it was the simplest method for the prototype.