Public Address System

A public address or PA system is a combination of a set of audio equipment that allows broadcasts over a designated area. Often found in schools, office buildings, Malls. PA systems can be used for announcements or emergency information and provide a simple way to get information out quickly. PA systems can be basic or advanced, and can be adapted to fit a variety of needs.

Basic PA systems are comprised of loudspeakers placed in convenient locations around the broadcasting area, an amplifier to increase the sound, and a mixer, which allows variation in sound levels. The user speaks into a microphone, and the sound is transmitted through connected cables to the area surrounding the speakers. Some systems also include microphones or intercoms near the speaker locations, allowing the listener to reply to the central location, although not to the entire system.