Multi-channel reverberation for computer music applications

Abstract

Reverberation is perhaps the most important post-production tool available to the sound engineer or computer musician. Geometrical methods are often used to model the acoustic properties of a room, including reverberation, but are limited to being valid only for high frequencies. At low frequencies, diffraction and the effects of room modes cannot be neglected. A method for modelling the two-dimensional propagation of sound within an enclosed room is presented which encompasses both of these particular properties by making use of a digital waveguide model. It is also possible to directionally encode the output from the room for processing music in a multi-channel surround-sound environment. A particular feature of this model is that the acoustic properties of the room can be explored and modified by means of a visual interface in a manner that is highly intuitive for musicians or those without an extensive knowledge of musical acoustics.