Perceptually plausible acoustics simulation of single and coupled rooms

Abstract

The fast and perceptually plausible room acoustics simulator [RAZR, see Wendt et al., JAES 62, 11 (2014)] has been optimized and extended to simulate the acoustics of connected rooms. RAZR synthesizes binaural room impulse responses (BRIRs) with high computational efficiency using a hybrid approach: early reflections are calculated as image sources for a shoebox-room approximation up to a low order, and the later reverberation is generated by a binaurally extended feedback delay network (FDN). For the extension toward two coupled rooms, validity, visibility, and diffraction of the image sources in the two rooms were taken into account, as well as different reverberation properties and the opening angle of the door to the neighbor room seen from a specific receiver position. The suggested method was evaluated by comparing measured and synthesized BRIRs for several rooms differing in size and reverberation time. For room acoustical parameters such as early decay time, late decay time, definition, and clarity a good agreement in terms of the Pearson correlation coefficient (0.86—0.99) was achieved between measured and simulated BRIRs. Subjective listening tests showed a good agreement of ratings of perceptual attributes (e.g., tone-color, reverberation time, envelopment, and naturalness) for the measured and synthesized BRIRs.