Dependence of Subject and Measurement Position in Binaural Signal Acquisition

A detailed evaluation of the dependence of the head-related transfer functions (HRTFs) on the position of the recording microphone along the ear canal for blocked and unblocked conditions is presented. Measurements at 250 source locations for a KEMAR mannequin and at 125 locations for two human subjects were performed. Conditions under which the magnitude transfer function from the HRTF acquisition position to the eardrum is essentially independent of the source location are shown quantitatively. These results are in agreement with and provide an extensive validation of other studies. The cause and magnitude of measurement errors are also analyzed in detail, and it is shown that these errors are subject dependent.