PUBLIC ADDRESS SYSTEM

loudspeaker system, warning system, system for broadcasting messages over loudspeakers

mechanized system for amplifying sound in public or large areas

A public address or "PA" system is an electronic amplification system with a mixer, amplifier and loudspeakers, used to reinforce a given sound (e.g.,a person making a speech, prerecorded music, or message) and distributing the 'sound' to the general public around a building. Simple PA systems are often used in small venues such as school auditoriums, churches, and small bars. PA systems with a larger number of speakers are widely used in institutional and commercial buildings, to read announcements or declare states of emergency. Intercom systems, which are often used in schools, also have microphones in each room so that the occupants can reply to the central office.
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Noun
1. an electronic amplification system used as a communication system in public areas
(synonym) P.A. system, PA system, P.A., PA
(hypernym) communication system
(part-meronym) amplifier

Environmental Protection Agency (USA) Administers (among many other things) the Toxic Substances Control Actis Biotechnology Program. (see: TSCA)

Synonyms and related words:
Gramophone, PA, PA system, Victrola, audio sound system, audiophile, binaural system, bitch box, bullhorn, cartridge, ceramic pickup, changer, crystal pickup, derived four-channel system, discrete four-channel system, four-channel stereo system, hi-fi, hi-fi fan, high-fidelity, intercom, intercommunication system, jukebox, magnetic pickup, monaural system, mono, needle, nickelodeon, phonograph, photoelectric pickup, pickup, quadraphonic sound system, radio-phonograph combination, record changer, record player, sound reproduction system, sound truck, squawk box, stereo, stylus, system, tape deck, tape recorder, tone arm, transcription turntable, turntable