audio amplifier - an amplifier that increases the amplitude of reproduced sound

booster amplifier, booster stations, boosters, relay links, relay stations, relay transmitters - an amplifier for restoring the strength of a transmitted signal

electronic equipment - equipment that involves the controlled conduction of electrons (especially in a gas or vacuum or semiconductor)

maser - an acronym for microwave amplification by stimulated emission of radiation; an amplifier that works on the same principle as a laser and emits coherent microwave radiation

P.A., P.A. system, PA system, public address system, PA - an electronic amplification system used as a communication system in public areas

radio receiver, radio set, receiving set, tuner, radio, wireless - an electronic receiver that detects and demodulates and amplifies transmitted signals

stereo, stereo system, stereophonic system - reproducer in which two microphones feed two or more loudspeakers to give a three-dimensional effect to the sound