ISpVoice::SetRate (SAPI 5.4)
Microsoft Speech API 5.4
ISpVoice::SetRate retrieves the current text rendering rate adjustment. The default rate for a voice is set through Speech properties in Control Panel.
HRESULT SetRate( long RateAdjust );
[in] Value specifying the speaking rate of the voice. Supported values range from -10 to 10 - values outside this range may be truncated.
Voices do not all have the same default rate.
The granularity of the rate is engine dependent.
Applications can adjust the rate of a voice either through this function call, or through XML passed to the voice with the input text of a speak call (see the XML Schema : SAPI white paper). The voice should combine rate adjustments made in these two ways to arrive at a final rate.