an instrument for converting sound waves into electrical energy variations which may then be amplified, transmitted, or recorded.

is a device for the mechanical recording and reproduction of sound.

An electrical device worn on the ear to receive radio or telephone communications or to listen to a radio, MP3 player, etc., without other people hearing.

A microphone designed to be used underwater for recording or listening to underwater sound.

From 1903 to 1910, as gramophone records were beginning to be released, over a third of them were "tango" music.

At first it was usual to join the microphone transmitter in the direct circuit.

In air, sound pressure can be measured using a microphone, and in water with a hydrophone.