
Via Boing Boing.
EVERYTHING SYNTH
"In 1985, Fairlight Instruments introduced the Voicetracker VT-5, a device that allows you to operate MIDI and control voltage synthesizers with your voice or any monophonic instrument, rather than with a MIDI keyboard. It was priced at US$2495 when it first came out.
The Voicetracker's 8MHz 68008 CPU analyzes an input signal to determine the pitch and harmonic content of the sound (such as dynamics and breathiness). It takes about 1ms plus several cycles of the incoming sound to determine the pitch. As you might guess, the pitch information is output as MIDI note values and analog control voltages, while the harmonic content analysis can be used to control a synthesizer's filters (among other things)."
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