#public_address_system__PA_system__PA  an electronic amplification system used as a communication system in public areas
  supertype:  communication_system__communicationsystem  a system for communicating
  part:  amplifier  electronic equipment that increases strength of signals passing through it
  part:  loudspeaker_system__loudspeakersystem__loudspeaker__speaker__speaker_unit__speakerunit__speaker_system__speakersystem  electro-acoustic transducer that converts electrical signals into sounds loud enough to be heard at a distance
  part:  tannoy  (British) a loudspeaker

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