This talk gives an overview on the acoustics aspects of this virtual reality system. This includes the simulation of room acoustics, sound reproduction to the user and the required signal processing. The real-time auralization engine enables a physically accurate simulation of sound propagation, including important wave effects such as sound scattering, airborne sound insulation between rooms and sound diffraction. Binaural synthesis is used to create a spatial sound playback. Audio rendering with long room impulse responses is achieved by highly parallelized non-uniformly partitioned convolutions. A dynamic crosstalk cancellation system allows to playback the binaural signals to the user without the need of headphones. In order to handle the significant computational complexity, the computation is distributed on a PC-cluster, that drives the simulation in real-time even for huge audio-visual scenarios. Several examples of applications are presented in the talk.