Mismatch between Interaural Level Differences Derived from Human Heads and Spherical Models

Bomhardt R, Fels J. Mismatch between Interaural Level Differences Derived from Human Heads and Spherical Models. In: AES Convention 140. Audio Engineering Society; 2016. Paper 9522. Available from: https://aes.org/publications/elibrary-page/?id=18221

@inproceedings{Bomhardt2016_18221,
  author = {Bomhardt, Ramona and Fels, Janina},
  title = {{Mismatch between Interaural Level Differences Derived from Human Heads and Spherical Models}},
  booktitle = {AES Convention 140},
  note = {Paper 9522},
  year = {2016},
  month = may,
  publisher = {Audio Engineering Society},
  url = {https://aes.org/publications/elibrary-page/?id=18221}
}

TY  - CPAPER
TI  - Mismatch between Interaural Level Differences Derived from Human Heads and Spherical Models
AU  - Bomhardt, Ramona
AU  - Fels, Janina
T2  - AES Convention 140
M1  - Paper 9522
PY  - 2016
DA  - 2016/05/06
UR  - https://aes.org/publications/elibrary-page/?id=18221
PB  - Audio Engineering Society
LA  - en
AB  - The individualization of head-related transfer functions (HRTFs) is important for binaural reproduction to reduce measurement efforts and localization errors. One common assumption of individualization for frequencies below 6 kHz is that the sound pressure field around a sphere is similar to the one of a human head. To investigate the accuracy of this approximation, this paper compares the frequency-dependent interaural level difference (ILD) from a spherical approximation, a simulation using magnetic resonance imaging and individually measured HRTFs of 23 adults' heads. With this database, it is possible to analyze the influence of the head shape and the pinna on ILD using the boundary element method and the measured HRTFs. Meanwhile the mismatch between the spherical and human ILD below 1.5 kHz in the horizontal plane is small, they differ above. In the frequency range of 1.5 and 3.5 kHz, ILD of one side of the head is dominated by two maxima. The offset of the ear canal entrance towards the back of the head and the depth of the head are the two major influencing factors. In general, it is observed that the maxima of a spherical ILD are much smaller and more widely spaced than in the human ILD. Above 4 kHz the difference between human and spherical ILDs is even stronger.
ER  -