Sets or gets the default maximal distance for 3D sounds. This value influences how loud a sound is heard based on its distance. See ISound::setMaxDistance() for details about what the max distance is. It is also possible to influence this default value for every sound file using ISoundSource::setDefaultMaxDistance(). This method only influences the initial distance value of sounds. For changing the distance after the sound has been started to play, use ISound::setMaxDistance() and ISound::setMaxDistance().