Property Reference - CSS Reference - page 303

Name
voice-balance
Values:
<number> | left | center | right | leftwards | rightwards
Initial value:
center
Applies to:
All elements
Inherited:
Yes
Computed value:
Not specified, but most likely an absolute number
Description:
Defines the stereo balancing of a speaking voice. This allows a voice to be shifted all the way
to one side or the other, or (with a <number>) to some mix of the two sides. For example,
−50 would cause the voice to sound as if it is coming from the center-left position. <num-
ber> values are constrained to the range −100 to 100, inclusive. The keyword left is equival-
ent to −100 ; right to 100 . The keyword leftwards subtracts 20 from the inherited value of
voice-balance; rightwards add 20.
This property applies to audio cues (see cue and related properties).
Examples:
.beck {voice-balance: right;}
.moore {voice-balance: left;}