A public address system (or PA system) is an electronic system comprising microphones, amplifiers, loudspeakers, and related equipment. It increases the apparent volume (loudness) of a human voice, musical instrument, or other acoustic sound source or recorded sound or music.

 PA systems — are specially designed mixer, amplifier, and speaker combinations used to communicate with an audience. Typical speakers like portable Bluetooth® speakers are used to simply play back prerecorded audio, like streaming music.