Binaural sound reproduction using head-related transfer functions (HRTFs) approximated by IIR filters

We propose a method using an IIR filter for simple realization of sound image localization. The head-related transfer functions (HRTFs) of a dummy-head are approximated by third to seventh-order IIR filters. The binaural signal sounds using the approximated HRTFs are reproduced via two loudspeakers, and sound image localization on the horizontal plane is realized. Experiments on the direction and the elevation angle of the sound image are carried out with 3 subjects. The results of the experiments show that the localization on the horizontal plane using the approximated HRTFs is of the same accuracy as the case of FIR filters that simulate the HRTFs.