More and more applications use virtual reality environments including spatial sound as a user interface. The demand for animations with impressive and immersive sound increases, as audio-visual equipment which can produce such effects becomes increasingly available. Spatial sound has migrated from special platforms to everyone's desktop. This is due to better general-purpose processors, which allow spatial sound processing in software, and hardware support, in the form of audio cards.
Wide distribution of content including spatial sound for virtual reality environments over the internet was made possible with the introduction of the Virtual Reality Modeling Language (VRML 2.0 [Bell et al. 96]). Even though the specification does not cover all aspects of spatial sound, dramatic effects can be produced. Available tools for producing VRML content have some support for spatial sound authoring, but in general they are not sufficient. We have developed widgets [Conner et al. 92], user interface objects with encapsulated geometry and behavior, to control and show properties of soundscapes and sound objects.