W3C CSS2 Cascading Style Sheets, level 2 - instructional media + ...

far-right
Same as ’60deg’. With ’behind’, ’120deg’.
right-side
Same as ’90deg’. With ’behind’, ’90deg’.
leftwards
Moves the sound to the left, relative to the current angle. More precisely,
subtracts 20 degrees. Arithmetic is carried out modulo 360 degrees. Note
that ’leftwards’ is more accurately described as "turned counter-clockwise,"
since it always subtracts 20 degrees, even if the inherited azimuth is already
behind the listener (in which case the sound actually appears to move to the
right).
rightwards
Moves the sound to the right, relative to the current angle. More precisely,
adds 20 degrees. See ’leftwards’ for arithmetic.
This property is most likely to be implemented by mixing the same signal into
different channels at differing volumes. It might also use phase shifting, digital
delay, and other such techniques to provide the illusion of a sound stage. The
precise means used to achieve this effect and the number of speakers used to
do so are user agent-dependent; this property merely identifies the desired end
result.
Example(s):
H1 { azimuth: 30deg }
TD.a { azimuth: far-right } /* 60deg */
#12 { azimuth: behind far-right } /* 120deg */
P.comment { azimuth: behind } /* 180deg */
If spatial-azimuth is specified and the output device cannot produce sounds
behind the listening position, user agents should convert values in the rearwards
hemisphere to forwards hemisphere values. One method is as follows:
if 90deg < x