rate

Specifies the speaking rate, where lower values are slower speaking rates.

Value

Integer: 1–100.

Lower values request slower speaking rates.

DEFAULT: 50

How to set

Shown in precedence order (see Rules of parameter precedence):

Set in a VoiceXML application, using the rate attribute of an SSML <prosody> element.

Set in the voice browser, using the Prosody-Rate header in a SPEAK method.

Set in the session xml file for the application. Configure the <speechsynth> element located under <sessionparameters>, <speechserver>.

Usage

Seldom used.

Speaking rates can significantly degrade speech quality (degrading the spectrum as a side-effect of the rate change). Avoid changes when possible. If necessary, make small changes and do listening tests for each voice. The speech quality degradation is specific to the voice characteristics: you must test every voice after changing the rate.