A systematic study of binaural reproduction systems through loudspeakers

Several approaches to render binaural signals through loudspeakers have been proposed in the past decades. Some studies have focused on the optimum loudspeaker arrangement while others have proposed more efficient filters. However, to our knowledge, the identification of optimal parameters for crosstalk cancellation filters applied to different loudspeakers configurations has not yet been addressed systematically. In this paper, we document a study of three different inversion techniques applied to several loudspeaker arrangements. Least square approximations in frequency and time domain are evaluated along with a crosstalk canceler based on minimum-phase approximation with a frequency independent delay. The three methods were applied to loudspeaker configurations with two-channel and the least square approaches to configurations with four channels. Several different span angles and elevations were simulated for each case. In order to obtain optimum parameters, we varied the bandwidth, filter length and regularization constant for each loudspeaker configuration and each method. We present in this paper a description of the simulations performed and the obtained results. The simulation results are documented in terms of the channel separation index, optimum regularization constant and performance error.