Sound signal processing for a virtual room

This paper presents the audio system built for the virtual room at Helsinki University of Technology. First we discuss the general problems for multichannel sound reproduction caused by the construction of, and the equipment in virtual rooms. We also describe the acoustics of the room in question, and the effect of the back-projected screens and reverberation to the sound. Compensation of the spectral deficiencies and the problems with the large listening area and high frequency attenuation are introduced. The hardware configuration used for sound reproduction is shortly described. We also report the software applications and libraries built for sound signal processing and 3-D sound reproduction.