You can obtain the pitch modulation by using the GetSpeechInfo function with the soPitchMod speech information selector, and you can change the pitch modulation by using the SetSpeechInfo function with the same selector. The speech volume of a speech channel is the average amplitude at which the channel generates speech. Volumes are expressed in fixed-point units ranging from 0.0 through 1.0. A ranging from 0.0 through 1.0. A value of 0.0 corresponds to silence, and a value of 1.0 corresponds to the maximum possible volume.
Volume units lie on a scale that is linear with amplitude or voltage.
A doubling of perceived loudness corresponds to a doubling of the volume. Note that just as a speech synthesizer does not generate speech at a constant frequency, it does not generate speech at a constant amplitude. Even when the speech rate is high, brief pauses break up a steady stream of speech. The speech volume is, like speech pitch, an indicator of an average. There is no way to determine or change the modulation of speech volume.