Microphones are most important part of public address system which are used for each and every applications and programmes. Technically, a microphone is a device that converts variations in sound “either airborne sound or sound from a resonating body, such as the front of an acoustic guitar” into variations in voltage.
Microphones are used to convert sound into an electrical form so that it can be amplified, processed, and mixed with other sounds before it is converted back into sound by loudspeakers.