A

David

Darling

loudspeaker

loudspeaker

A loudspeaker, or speaker, is a device to convert electrical impulses into sound. It commonly comprises a rigid conical diaphragm attached to a coil held such that it may move backward and forward; within the cylinder of the coil is a fixed permanent magnet. Changes in the current supplied to the coil alter its magnetic field so that it, and the cone, vibrate to produce the compression waves that are sound. High fidelity sets use two or more loudspeakers of different sizes for more accurate reproduction.