Sets the speech pitch on a designated speech channel.


func SetSpeechPitch(_ chan: SpeechChannel, _ pitch: Fixed) -> OSErr



The speech channel whose pitch you wish to set.


The new pitch for the speech channel, expressed as a fixed-point frequency value.

Return Value

A result code. See Result Codes.


The SetSpeechPitch function changes the current speech pitch on the speech channel specified by the chan parameter to the pitch specified by the pitch parameter. Typical voice frequencies range from around 90 hertz for a low-pitched male voice to perhaps 300 hertz for a high-pitched child’s voice. These frequencies correspond to approximate pitch values in the ranges of 30.000 to 40.000 and 55.000 to 65.000, respectively. Although fixed-point values allow you to specify a wide range of pitches, not all synthesizers will support the full range of pitches. If your application specifies a pitch that a synthesizer cannot handle, it may adjust the pitch to fit within an acceptable range.

See Also

Changing Speech Attributes

func SetSpeechProperty(SpeechChannel, CFString, CFTypeRef?) -> OSErr

Sets the value of the specified speech-channel property.

func SetSpeechRate(SpeechChannel, Fixed) -> OSErr

Sets the speech rate of a designated speech channel.