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Pattern Playback

PHONETICS: Early speech synthesiser developed at Haskins Laboratories (during and after the second world war). Speech was synthesised by converting patterns (stylised spectrograms) painted on acetate film loops into acoustic signals by a photoelectric system. The synthesiser was used to systematically vary the acoustic parameters of speech to determine the cues used in speech perception.

More on Pattern Playback and audiodemonstration
Audiodemonstration Pattern Playback