loudspeaker

n. electronic device which amplifies sound

For the Marty Friedman album, see Loudspeaker (album) A loudspeaker, speaker, or speaker system is an electromechanical transducer that converts an electrical signal into sound. The term loudspeaker can refer to individual devices (or drivers), and complete systems consisting of an enclosure incorporating one or more drivers and additional electronics. Loudspeakers are the most variable elements in any audio system, and are responsible for marked audible differences between otherwise identical sound systems. Loudspeaker performance (i.e., their accuracy in reproducing a signal without adding distortion) is significantly poorer than that of other audio equipment. For example, harmonic distortion in a typical loudspeaker can be 100 to 1000 times greater than that of amplifiers. The frequency response of a loudspeaker is often referenced as being within ±3 dB of perfect linearity (though many speaker designs fall far outside this range), whereas an amplifier may vary less than 0.1 dB.
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Noun
1. electro-acoustic transducer that converts electrical signals into sounds loud enough to be heard at a distance
(synonym) speaker, speaker unit, loudspeaker system, speaker system
(hypernym) electro-acoustic transducer
(hyponym) bullhorn, loud-hailer
(part-holonym) public address system, P.A. system, PA system, P.A., PA