Originally vocoders were designed to analyze the human voice, in order to to conserve bandwidth and encrypt radio transmissions – it was even used in the military. But then, in the 70’s, Kraftwerk decided to use it to make robot music from the future. Here’s more from Sonic State:

In 1978, Moog created their first commercially-available Vocoder named the ‘Moog 16 Channel Vocoder‘ in partnership with composer Wendy Carlos, and based on the schematics by Homer Dudley. It featured 16 patchable bands from 50 to 5,080 Hz, with a direct mode to pass higher frequencies for greater clarity and articulation – with controls for hiss, buzz, and balance. The Moog 16 can be heard on the likes of Giorgio Moroder’s E=MC2 as well as the soundtrack of Stanley Kubrik’s controversial adaption of ‘A Clockwork Orange’.

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