A benchmark study on room acoustic simulations with various material input complexities

This work investigates and evaluates the capabilities of an explicit finite-difference time-domain (FDTD), a fast multipole indirect boundary element method (FMBEM), and a ray-tracing (RT) solver in the context of room acoustic modeling and simulations. In room acoustic simulations, the wave-based FDTD and FMEBM methods are known for generating accurate results at low frequencies, while the RT technique is in principle more valid at higher frequencies. The numerical aspects of setting up the solutions for each solver are discussed. Special attention is given to the influence of material input data of various degrees of detail. Single/multiple frequency-independent/dependent materials are considered in the model setup. The modeling capabilities of the three solvers in handling material input with various complexities are analyzed. Numerical results are evaluated in both frequency and time domains. Room acoustic parameters, including the reverberation time (T_20), early decay time (EDT), clarity (C_80), and definition (D_50), are compared. These results are also compared with available measurement data. Last but not least, the computational efficiencies of the three solvers are briefly discussed.