Patent ID: 7885418

Claim:
A loudspeaker assembly comprising: Movable high pressure boundaries with a small total working surface area relative to a movable acoustic radiating diaphragm, sealed to, freely movable longitudinally within, and pressurized by a fixed cylinder that is pneumatically coupled with and pressurized by a pressure vessel of preferred volume containing vapor or gas at a high pressure relative to prevailing atmospheric pressure; a vacuum chamber with substantially evacuated conditions whose pressure boundaries include the movable acoustic radiating diaphragm assembly; the movable acoustic radiating diaphragm assembly with a majority of its internal surface area exposed to the substantially evacuated conditions and a minority of its internal surface area acting against the movable high pressure boundaries, via a mechanical couple wherein as pressure within the pressure vessel is increased by inward displacement of the movable high pressure boundaries, the total working surface area of these boundaries, on which the gas or vapor acts to impede inward movement, diminishes and as pressure within the pressure vessel is reduced by outward displacement of the movable high pressure boundaries, the total working surface area of these boundaries, on which the gas or vapor acts to facilitate outward movement, increases; a magnetic system for actuating the acoustic diaphragm assembly via a voice-coil and associated former.