A public address system (PA system) is an Electronic Sound amplification with the microphone, Amplifier and loud speakers used to allow a person to speak to a large public. A best public address system consist of input sources Amplifier and monitoring equipment loud speakers. These input sources are fed into preamplifiers and signal routers that determine the zones to which the audio signal is fed. The pre amplified signals are then passed into the amplifiers. This control equipment is also used for separating zones in a PA system.