A method of interpolating binaural impulse responses for moving sound images

Abstract

Previously introduced method of interpolating binaural impulse responses and algorithm to simulate a moving sound image were evaluated objectively. The method interpolates the responses taking into account the arrival time difference due to changes in the direction of a moving sound source. For the angular interval of 15°, the average of the SDR values of our method, 23 dB was larger than that of the simple method, 9.9 dB. The variances of the SDR values showed our method interpolated the responses more independently of the azimuths of the sound source than the simple method. The responses interpolated using our method changed smoothly as the source direction changed. We have evaluated the algorithm by comparing a moving sound image simulated using the algorithm with an actual moving sound image recorded using a rotating dummy head and with a moving sound image simulated using a conventional method. The spectrogram of the binaural signal of the moving sound image, and no ripples were seen.