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The female voice.
The vast majority of projects in speech
synthesis have used male voices. The early
synthesizers of the 1980s were very limited in the
kind of speech they could cope with. The Haskins
Laboratories Pattern Playback, for example, could
only produce a fundamental frequency of 120Hz.
______, very little information was available on the
acoustics of female speech. ______ several efforts
were made to produce female-sounding speech, none
of them was convincing.______, since the 1980s, the
use of more sophisticated acoustic analyses and
equipment has led to the synthesis of several
utterances with an acceptable female quality.
(Adapted from: The Cambridge Encyclopedia of
Language)