Microphone

A microphone, colloquially called a mic (), or mike, is a transducer that converts sound into an electrical signal. Microphones are used in telecommunication, sound recording, broadcasting, and consumer electronics, including telephones, hearing aids, and mobile devices.

Several types of microphone are used today, which employ different methods to convert the air pressure variations of a sound wave to an electrical signal. The most common are the dynamic microphone, which uses a coil of wire suspended in a magnetic field; the condenser microphone, which uses the vibrating diaphragm as a capacitor plate; and the contact microphone, which uses a crystal of piezoelectric material. Microphones typically need to be connected to a preamplifier before the signal can be recorded or reproduced.