speaker without a magnet

[fareezaw]

dears
pls I want to know how can speaker works without a magnet ?
how the coil moves ( what is the law )?
also if you have any link for drawing please advise
new freind
fareez

 

[highfigh]

dears
pls I want to know how can speaker works without a magnet ?
how the coil moves ( what is the law )?
also if you have any link for drawing please advise
new freind
fareez

If the box has another woofer with a magnet, the one you're asking about may be a passive radiator. If not, it may have come off, somehow. Does it have a voice coil?

 

[Adam]

Welcome to the forum!

Do you have one that is like that and want to understand it, or are you wanting to design one like that?

 

[croseiv]

Never heard of this with a "standard" speaker, but there are ribbon and elctrostatic jobbies.

 

[irishtom]

Ribbons use magnets. Electrostats, piezos and plasmas avoid magnets; there may be other technolgies that do, I dunno.

 

[skizzerflake]

At one time there was also Plasmatronics speakers. They used used some sort of high voltage generator to heat plasma state helium and produce waves in air. The things were huge, expensive and needed to be hooked to a big helium tank. They emitted helium so eventually the occupants started to talk like Munchkins. They were also rumored to emit ozone, which is corrosive and mildly toxic. I don't think they had magnets though. Quite an overkill.

 

[fareezaw]

At one time there was also Plasmatronics speakers. They used used some sort of high voltage generator to heat plasma state helium and produce waves in air. The things were huge, expensive and needed to be hooked to a big helium tank. They emitted helium so eventually the occupants started to talk like Munchkins. They were also rumored to emit ozone, which is corrosive and mildly toxic. I don't think they had magnets though. Quite an overkill.

dear
thank you
I sell and repair speakers, but now I receive this new type and I want to know more information about
regards

 

[highfigh]

At one time there was also Plasmatronics speakers. They used used some sort of high voltage generator to heat plasma state helium and produce waves in air. The things were huge, expensive and needed to be hooked to a big helium tank. They emitted helium so eventually the occupants started to talk like Munchkins. They were also rumored to emit ozone, which is corrosive and mildly toxic. I don't think they had magnets though. Quite an overkill.

Sounds like the speakers my dad saw/heard at a HiFi expo in the mid-'50s, made by Voice of Music.