Reduced-memory early reflection and reverberation simulator and method

Abstract

Early reflection and reverberation processing using a decimating filter simulates the high frequency attenuation of an actual physical and acoustical environment and advantageously reduces the memory storage and computational burden of the early reflection and reverberation processing method. A method of generating a reverberation effect in a sound signal includes decimating the sound signal in the sound signal path and forming an early reflection sound signal from the decimated sound signal. The early reflection sound signal has a reduced sample rate an attenuated high frequency components in comparison to the sound signal. The method further includes decimating the early reflection sound signal, recirculating the decimated early reflection sound signal in a plurality of iterations with a delay and a gain imposed between the iterations to form a reverberated sound signal, interpolating the early reflection sound signal and the reverberated sound signal, and accumulating the reverberated sound signal, the early reflection sound signal, and the sound signal to form a reflection and reverberation-enhanced sound signal. An audio signal processor processes a sound signal supplied to a sound signal path. The audio signal processor includes an early reflection processor connected to the sound signal path to receive the sound signal and simulate an early reflection signal, a reverberator connected to the early reflection processor to receive the early reflection signal and simulate a reverberation signal, and a summer connected to the sound signal path, the early reflection processor, and the reverberator. The early reflection processor and reverberator include a decimator for decimating the incoming signal.