How speakers & microphones work

The simply symmetry of speakers and microphones.


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All sounds are produced by vibrations. With a permanent magnet and an electromagnet produced by current flowing through a coil of wire, speakers convert an electrical signal into tiny vibrations, which are conveyed to the surrounding air by an attached diaphragm. We interpret these vibrations travelling through the air as sound. Microphones use the same concept in reverse, with vibrations from the air causing a diaphragm, and hence a wire coil, to move, This movement relative to the permanent magnet generates a varying electrical current.

18 and 19 August holiday workshops cancelled

Due to planned transport strikes, all holiday workshops on Thursday 18 and Friday 19 August are cancelled.