SCOOT: Classic Speech Synthesis

Was based on simulations of the vocal tract, with filters for the formants.  The simulation was supplied with parameters for excitation, formant frequencies and amplitudes.   There were tables specifying how the parameters should change with time for different phones. The technique was also called ‘Speech Synthesis by Rule’ or ‘Formant Synthesis’.

The best known systems were the Klatt Synthesiser (US, ) and the Holmes Synthesiser (UK).  Tutorial papers for both systems are in the Smithsonian Speech Synthesis History Project (SSSHP) 1986 – 2002

See this link  for Klatt and this link for Holmes

The Klatt synthesiser is familiar as the voice of Stephen Hawking, and provided the original ‘Dec Talk’ and  ‘Apple Voices’.