"Richard Tomkins" wrote in message ws.com...
Has any manufacturer ever designed/built a loudspeaker that reversed the
functions of the voicecoil and permanent magnet, such that the permanent
magnet was attached to the speaker cone and the electromagnet was the
stationary magnet?

What about having the voicecoil on the outside rim of the speaker rather
than on the inside? Has this ever been done?

Instead of using a single voicecoil in the center, how about one on the edge
and one in the middle?

How about a dual voice coil, one being driven and the second providing
feedback like a closed servo loop?

Regards, rtt


Way back in the day there were speakers with conventional voice
coils but that used a stationary electro-magnet instead of a permanent
magnet. In order to energize that stationary coil it was also used as
the filter inductor in the power supply.