Keynote Speech

Three-dimensional sound reproduction for individual listeners: personalization of head-related transfer functions

Invited Speaker

Prof. Kazuhiro Iida, Faculty of Engineering, Chiba Institute of Technology, Japan


A listener’s own head-related transfer functions (HRTFs) are required for accurate three-dimensional sound image control. The HRTFs of other listeners often cause front-back confusion and errors in the perception of vertical angles. However, measuring the HRTFs of all listeners for all directions of a sound source is impractical because the measurement requires a special apparatus and a lot of time. The present speech introduces some previously proposed methods for estimating the appropriate HRTFs for an individual listener. Among them, the method, which the author has proposed, is explained in detail. The method estimates the frequencies of the two lowest spectral notches (N1 and N2), which play an important role in vertical localization, in the HRTF of an individual listener by anthropometry of the listener’s pinnae. The best-matching HRTFs, of which N1 and N2 are the closest to the estimates, are then selected from an HRTF database. The results of localization tests in the median plane revealed that the best-matching HRTFs provided approximately the same performance as the listener’s own HRTFs.


Dr. Kazuhiro IIDA was born in Kyoto, Japan in 1961. He graduated at the graduate school of Kobe University and received his degree of Ph.D. in Engineering. He is a Professor of Chiba Institute of Technology. He is a board member of the Acoustical Society of Japan (2005-2009, 2015-), and a guest researcher of Science and Technology Research Laboratory of Japan Broadcasting Corporation (2015-). His research interests are spatial hearing, binaural hearing, head-related transfer function, architectural acoustics, electrical acoustics, psychological acoustics, and sound field simulation.