Variability of Head Related Transfer Functions across subjects
* Presenting author
The paper discusses across subject differences of measured Head Related Transfer Functions (HRTFs) in horizontal and vertical planes. The comparison was also done with reference to the results obtained with the use of an acoustic manikin. The work was done for an exemplary database available on-line and for the HRTFs measured with the use of a specific measurement setup in our laboratory. In the latter case, acquisition of HRTF pairs (left and right ear) was done at 370 sound source positions in the surrounding space with the use of two miniature microphones placed at the entrance to the blocked ear canal. Across subject differences of measured HRTFs were assessed in horizontal planes at various elevation angles. The results showed that HRTF is nearly symmetrical in the 300 Hz to 1 kHz frequency band. For frequencies above 1 kHz (more so above 5 kHz), as expected, the effect of interaural asymmetry increases due to filtering effect of complicated anatomical structures of pinnae. The influence of these effects differed among 15 subjects who participated in the study. The results obtained with the use of the acoustic manikin were not representative (as an average) for results with subjects.