Room impulse response synthesis based on a 2D multi-plane FDTD hybrid acoustic model

This paper exposes, and analyzes the validity of, a novel hybrid acoustic modeling system created through complementary assimilation of 3D geometric and 2D numerical modeling techniques. It is demonstrated that multiple 2D Finite Difference Time Domain schemes may be employed to simulate low-frequency sound wave propagation throughout a simplistic 3D enclosure, thus avoiding the immense computational challenges posed by 3D numerical approaches. Band limited room impulse responses (RIRs) generated in this way may be appropriately calibrated and combined with high-frequency results obtained from well-established geometric modeling methods to realize efficient, yet accurate hybrid RIR synthesis. Objective results show that the low-frequency 2D multiplane solution yields comparable accuracy to that gained through 3D simulation while achieving a run-time reduction of 99.15%.