Values are specified the same way as 'pause-before'. If only one value is given, it applies to both properties. NA Auditory icons are another way to distinguish semantic elements. The same sound can be used both before and after, using the cue property. 4 Spatial properties Spatial audio is an important stylistic property for aural presentation.
Stereo speakers produce a lateral soundstage.
VRML 2.0 also includes spatial audio, which implies that spatial audio hardware will become more widely available. 90deg is to the right, 180deg behind and 270deg to the left. 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 soundstage. The precise means used to acheive this effect and the number of speakers used to do so are browser dependent - this property merely identifies the desired end result.