Variability in the Headphone-to-Ear-Canal Transfer Function
Headphone-to-ear-canal transfer functions (HpTFs) for 20 headphone placements were measured for each ear of three participants and an acoustic manikin. Head-related transfer functions (HRTFs) were measured for nine sound-source locations within a 14.5~ radius of each of eight representative locations. Noises were convolved with these functions and passed through a cochlear filter model to estimate cochlear excitation. The variability of the magnitudes of the filtered HpTFs was much less than the variability of the magnitudes of the unfiltered HpTFs. It was also considerably less than the variability of the magnitudes of the filtered HRTFs. In addition, the variability of the group delays of the HpTFs for the three human participants was considerably less than the minimum discriminable interaural time difference. It follows that much of the information in HRTFs that could provide a cue to sound-source location will not be masked by the variability of HpTFs across headphone placements. The spatial fidelity of an individualized virtual audio display, therefore, will not necessarily be compromised by variability in HpTFs.
Click to purchase paper or login as an AES member. If your company or school subscribes to the AES Journal then you can look for this paper in the institutional version of the Online Journal. If you are not an AES member and would like to subscribe to the E-Library then Join the AES!
This paper costs $20 for non-members, $5 for AES members and is free for E-Library subscribers.