Explanation:

The Sound node describes the positioning and spatial presentation of sound VRML scene. The sound has a location (default is origin) from which it originates. It is emitted from this point location in a spherical or ellipsoid pattern as dictated by the minBack, minFront, maxBack, maxFront and direction parameters.

The source field specifies the sound source. This must be either an AudioClip or a MovieTexture whose format supports sound.

minBack, minFront specify the size of an inner region centered at the location of the sound. Within this region the sound is heard at full intensity.

maxBack, maxFront specify an outer region. As one moves from the inner to the outer region the sound tapers off, and outside the outer region it is not heard.

The Sound node is just like any other element of the scene graph in that it can be heard only when it is part of the current scene. Thus it can be disabled via an LOD or Switch node, for example.