Aerophone

A"ër*o*phone`, n. [Aëro- + Gr. voice.] (a) A form of combined speaking and ear trumpet. (b) An instrument, proposed by Edison, for greatly intensifying speech. It consists of a phonograph diaphragm so arranged that its action opens and closes valves, producing synchronous air blasts sufficient to operate a larger diaphragm with greater amplitude of vibration.