Property Reference - CSS Reference - page 308

Name
voice-pitch-range
Values:
<number> | <percentage> | x-low | low | medium | high | x-high
Initial value:
User agent-dependent
Applies to:
All elements
Inherited:
Yes
Percentages:
Refer to the inherited value
Computed value:
Not specified, but likely an absolute number
Description:
Defines the variation in average pitch used by the speaking voice while audibly rendering the
element's content. The higher the variation, the more animated the voice will sound. <num-
ber> values define a pitch range in hertz.
Examples:
em {voice-pitch-range: high;}
code {voice-pitch-range: 50;}