Public address system

Public address system

The public address system (PA system) is an electronic system that includes a microphone, amplifier, speakers, and peripherals. This system enhances the apparent volume of vocals, musical instruments, other sound sources like recorded sounds and music. The sound enhancement system can be used in public places such as announcers and performers. Typical applications include sports fields, public transportation, facilities, live or recorded music venues, and events. A PA system may include multiple microphones or other sources, a mixer for integrating and switching multiple sources, and multiple amplifiers and speakers for high volume or wide distribution.

Simple public address systems are commonly used in small rooms such as school rooms, churches, and small bars. Acoustic reinforcement systems with multiple speakers are widely used for presentations in public, institutional, and commercial buildings, as well as in schools, stadiums, cruise ships, and aircraft. Intercom systems installed in many buildings have speakers throughout the building, and many rooms have microphones so residents can respond to notifications. Public address and intercom systems are commonly used in emergency communication systems.