Cross‐talk Cancellation Algorithm for 3D Sound Reproduction

If the right and left signals of a binaural sound recording are reproduced through loudspeakers instead of a headphone, they are inevitably mixed during their transmission to the ears of the listener. This degrades the desired realism in the sound reproduction system, which is commonly called ‘cross‐talk.’ A ‘cross‐talk canceler’ that filters binaural signals before they are sent to the sound sources is needed to prevent cross‐talk. A cross‐talk canceler equalizes the resulting sound around the listener's ears as if the original binaural signal sound is reproduced next to the ears of listener. A cross‐talk canceler is also a solution to the problem—how binaural sound is distributed to more than 2 channels that drive sound sources. This paper presents an effective way of building a cross‐talk canceler in which geometric information, including locations of the listener and multiple loudspeakers, is divided into angular information and distance information. The presented method makes a database in an off‐line way using an adaptive filtering technique and Head Related Transfer Functions. Though the database is mainly concerned about the situation where loudspeakers are located on a standard radius from the listener, it can be used for general radius cases after a distance compensation process, which requires a small amount of computation. Issues related to inverting a system to build a cross‐talk canceler are discussed and numerical results explaining the preferred configuration of a sound reproduction system for stereo loudspeakers are presented.