Public address system
electronic acoustic system for delivering audio to a large audience or area, either information (spoken) or music for entertainment
A public address system, commonly known as a PA system, is a network of sound devices that can play sound to several people. They are often used to make announcements in large buildings or neighbourhoods. In big spaces outdoors, amplifiers and loudspeakers have to be very loud. Otherwise the volume would be too small to be heard by everybody.
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