Diaphragm

When these variations reach a moving-coil microphone, they push and pull on a thin diaphragm, causing it to vibrate backwards and forwards.

In a moving-coil microphone, those pressure variations make a thin diaphragm vibrate backwards and forwards. A coil attached to the diaphragm moves with it, while a permanent magnet remains fixed. The coil therefore moves through the magnet’s field.

A dynamic microphone does this using electromagnetic induction. Its main working parts are a thin diaphragm, a coil of wire attached to the diaphragm and a permanent magnet that provides a magnetic field.

When they reach a moving-coil microphone, they make a thin diaphragm vibrate backwards and forwards. A coil attached to the diaphragm therefore moves with it inside the field of a permanent magnet.