Patent ID: 6111962
Filing Date: 2000-08-29
Classification: G10H,G10K

Abstract:
A reverberation system comprising:a storage device that stores a set of impulse responses of reverberant sound that are actually or virtually observed at a plurality of different observation positions in the vicinity of room partitions that define an actual or virtual model acoustic room;a reverberant sound producing device that produces reverberant sound that is supposed to be generated when sound emitted from a real sound source location inside a virtual acoustic room that is to be simulated, surrounded by virtual room partitions is reflected by the virtual room partitions, based on the impulse responses stored in said storage device; anda plurality of loudspeakers for producing reverberation, which are located at simulation positions that correspond to said plurality of different observation positions of said model acoustic room, said loudspeakers being oriented in directions in which the sound emitted from the real sound source location is reflected by said virtual room partitions,wherein said reverberant sound producing device comprises:a plurality of digital filters each of which processes a source signal representing the sound emitted from the real sound source location, according to a convolution algorithm, using coefficient parameters representing a corresponding one of the impulse responses of reverberant sound stored in said storage device, to thereby synthesize a virtual reverberant sound signal at each of said simulation positions;a plurality of signal delay devices that are respectively arranged in series with said plurality of digital filters, each of said signal delay devices giving a signal delay time to an output of a corresponding one of said digital filters; anda delay time setting device that controls the signal delay time of said each signal delay device, to thereby equivalently move at least part of the virtual room partitions of the virtual acoustic room toward or away from the real sound source location, and thus virtually change a shape of the virtual acoustic room into a desired shape, andwherein said reverberant sound producing device synthesizes respective reflected sounds from a plurality of imaginary sound sources, based on the sound emitted from the real sound source location, said imaginary sound sources being assumed to be present around the virtual acoustic room according to a relationship between the actual sound source location and a position of the at least part of the virtual room partitions, so that the reflected sound from each of the imaginary sound sources is reproduced from each of said plurality of loudspeakers, with time differences and level differences, to thereby produce virtual reverberation signals for respective ones of the simulation positions, and supply the virtual reverberation signals to respective ones of said plurality of loudspeakers.