Compression Driver

A type of loudspeaker designed to feed sound into an acoustic horn, or flared opening. A compression driver is designed to work in a 'compression mode', where the air immediately in front of the transducer diaphragm is constrained by the throat of the horn to create a high acoustic impedance. The horn acts as an acoustic transformer to couple the high impedance area in front of the driver to the low impedance of the atmosphere, optimising the power transfer and increasing efficiency significantly.