The ‘cue’ property is a shorthand for ‘cue-before’ and ‘cue-after’. If two values are given the first value is ‘cue-before’ and the second is ‘cue-after’. If only one value is given, it applies to both properties.

]]> The ‘cue-before’ and ‘cue-after’ properties specify auditory icons (i.e. pre-recorded / pre-generated sound clips) to be played before (or after) the selected element within the aural box model.

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]]> The ‘pause’ property is a shorthand property for ‘pause-before’ and ‘pause-after’. If two values are given, the first value is ‘pause-before’ and the second is ‘pause-after’. If only one value is given, it applies to both properties.

]]> The ‘pause-before’ and ‘pause-after’ properties specify a prosodic boundary (silence with a specific duration) that occurs before (or after) the speech synthesis rendition of the selected element, or if any ‘cue-before’ (or ‘cue-after’) is specified, before (or after) the cue within the aural box model.

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]]> The ‘rest’ property is a shorthand for ‘rest-before’ and ‘rest-after’. If two values are given, the first value is ‘rest-before’ and the second is ‘rest-after’. If only one value is given, it applies to both properties.

]]> The ‘rest-before’ and ‘rest-after’ properties specify a prosodic boundary (silence with a specific duration) that occurs before (or after) the speech synthesis rendition of an element within the aural box model.

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]]> The ‘speak’ property determines whether or not to render text aurally.

]]> The ‘speak-as’ property determines in what manner text gets rendered aurally, based upon a predefined list of possibilities.

]]> The ‘voice-balance’ property controls the spatial distribution of audio output across a lateral sound stage: one extremity is on the left, the other extremity is on the right hand side, relative to the listener's position. Authors can specify intermediary steps between left and right extremities, to represent the audio separation along the resulting left-right axis.

]]> The ‘voice-duration’ property specifies how long it should take to render the selected element's content (not including audio cues, pauses and rests ). Unless the value ‘auto’ is specified, this property takes precedence over the ‘voice-rate’ property, and should be used to determine a suitable speaking rate for the voice. An element for which the ‘voice-duration’ property value is not ‘auto’ may have descendants for which the ‘voice-duration’ and ‘voice-rate’ properties are specified, but these must be ignored. In other words, when a ‘time’ is specified for the ‘voice-duration’ of a selected element, it applies to the entire element subtree (children cannot override the property).

]]> The ‘voice-family’ property specifies a prioritized list of component values that are separated by commas to indicate that they are alternatives (this is analogous to ‘font-family’ in visual style sheets). Each component value potentially designates a speech synthesis voice instance, by specifying match criteria (see the voice selection section on this topic).

]]> The ‘voice-pitch’ property specifies the "baseline" pitch of the generated speech output, which depends on the used ‘voice-family’ instance, and varies across speech synthesis processors (it approximately corresponds to the average pitch of the output). For example, the common pitch for a male voice is around 120Hz, whereas it is around 210Hz for a female voice.

]]> The ‘voice-range’ property specifies the variability in the "baseline" pitch, i.e. how much the fundamental frequency may deviate from the average pitch of the speech output. The dynamic pitch range of the generated speech generally increases for a highly animated voice, for example when variations in inflection are used to convey meaning and emphasis in speech. Typically, a low range produces a flat, monotonic voice, whereas a high range produces an animated voice.

]]> The ‘voice-rate’ property manipulates the rate of generated synthetic speech in terms of words per minute.

]]> The ‘voice-stress’ property manipulates the strength of emphasis, which is normally applied using a combination of pitch change, timing changes, loudness and other acoustic differences. The precise meaning of the values therefore depend on the language being spoken.

]]> The ‘voice-volume’ property allows authors to control the amplitude of the audio waveform generated by the speech synthesiser, and is also used to adjust the relative volume level of audio cues within the aural box model of the selected element.

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