A public address system is an electronic system. It comprises microphones, loudspeakers, amplifiers, etc. PA systems are mainly used in public areas so that human voices or musical instruments can be audible over a large area. It is used by singers, performers during concerts or award functions. It can also be used in a school or university auditorium. A PA system includes multiple microphones, loudspeakers, mixing console to combine and multiply the volume over a much wider area.