Magnetless Subwoofers

How does a magnetless speaker/subwoofer work?

Thanks!

There is no such thing.  Loudspeakers require magnets to function.  Where did you see a "magnetless" woofer?

I suppose if you make the pannel large enough, you could make a subwoofer out of an electrostatic speaker.  Here's a link describing how they work: http://electronics.howstuffworks.com/question713.htm

The only other one I can think of is the prototype  Ionic speaker Adire Audio showed at CES this year.  But as it's a prototype of a developing, unreleased technology, you won't get a description how it works.

Not to pick nits Dave, but an electromagnet is indeed still a magnet, it just may not be a permanent one.  And Steven, I believe the plasma field speaker systems I have read about use magnetic deflection coils to focus the energy (not sure if the Adire experimental system do or not, though.) 

Coppellstereo, are you talking about some of the newer shallow-mount woofers that appear to be nearly flat?  These use an inverted motor system and the magnet assembly is located inside the "cone" area - so to speak.

No magnets at all.  It consists of one screen having a negative charge and the other having an AC signal voltage applied to it.

Phoenix Gold actually liscensed that technology from Servodrive.  It was a unique take however as the Servodrive units were belt driven models.  It does use magnets in the motor though.

Ah, so it's based on an ion pump to move the air.  Interesting.  I'll have to go see it one of these days!