Effects of Geometrical Acoustics Model Simplification on Binaural Reverberation

Virtual reverberation rendering typically requires detailed information about room geometry and surface acoustic characteristics. While comprehensive modeling approaches can account for all aspects of an acoustic environment, they often incur high computational cost that may be perceptually unnecessary. Therefore, finding a trade-off between perceptual authenticity and model complexity becomes a relevant challenge. This study investigates such compromise through the use of geometrical acoustics to render Ambisonics-based binaural reverberation. The accuracy of the rendering is determined, among other factors, by its fidelity to the room’s geometry and to the acoustic properties of its materials. In particular, the model fidelity is varied by simplifying the room geometry and frequency resolution of the absorption coefficients. Several decimated models based on a single room were perceptually evaluated using a multi-stimulus comparison method. Additionally, these differences were numerically assessed through the comparison of acoustic parameters of the rendered reverberation. According to numerical and perceptual evaluations, lowering the frequency resolution of absorption coefficients can have a significant impact on the perception of reverberation, while a smaller impact was observed when decimating the geometry of the model.