On the Use of a Hybrid Linear-ERB Frequency Scale for Lightweight Simulation of HRTFs

This paper explores a lightweight method for numerical simulation of HRTFs based on a hybrid linear-ERB frequency scale applied to the boundary element method. The HRTFs simulated according to our modified approach were evaluated by comparison with HRTFs acoustically measured and simulated using the standard linear scale. The HUTUBS dataset was used to assess differences in magnitude, interaural phase, and interaural time. We explored two approaches for phase at high frequencies: interpolation and extrapolation. The results suggest that extrapolation provides better overall agreement of the phase response in comparison to acoustic measurements and that using at least two bins per auditory band is sufficient to provide seamless approximations of the HRTFs simulated with the standard approach, with computing time savings of around 86%.