Reliability of Headphone Equalization in Virtual Sound Reproduction

Headphone equalization, which is accomplished by multiplying the inverse of headphone-to-ear-canal transfer functions (HpTFs), is necessary in headphone-presented virtual sound reproduction. Therefore, measurement accuracy of HpTFs is vital to guarantee an authentic virtual sound reproduction. To evaluate the perceptual influence of intra-individual differences in HpTF measurements on headphone equalization and hence virtual sound reproduction, repeated measurements of HpTFs were conducted on an artificial head and human subjects, and then were analyzed using perceptual-motivated objective comparisons in three frequency ranges. Moreover, a series of psychoacoustic experiments were carried out. Results indicate that the intra-subject differences in HpTFs are inaudible in any of the frequency ranges, suggesting a single measurement is perceptually adequate to represent the individual HpTF.