Admissible Range for Individualization of Head-Related Transfer Function in Median Plane

Abstract

Individualization of the head-related transfer function (HRTF) to each listener is important for the listener to localize sound sources accurately. If an inappropriate HRTF is used, the sound localization is incorrect and there is a lower sense of presence. We investigate the admissible ranges for individualization of P1, N1, and N2 frequencies, which are spectral cues of HRTFs to localize sounds, in particular, on the median plane. The admissible ranges for individualization are the valid ranges of the spectral cues on the HRTFs at which each listener can localize presented sounds. We did listening tests to estimate the admissible ranges of P1, N1 and N2. The results suggest that N1 should be accurate, the admissible range is narrow, P1 and N2 are not strict, and also that strict tuning of P1 and N2 is not required. When applying a reconstructed HRTF for a certain listener selected from those of others in the database based on the condition that the N1, N2, and P1 of those HRTFs are limited to the admissible ranges, accuracy of sound localization approaches that applying the most appropriate HRTF for the listener.