Perceptive approaches: the illusion of "phantom sources
Spatial sound reproduction

The most widely used model of spatial sound reproduction is still stereophony, using a pair of loudspeakers located in front of the listener [6] [7]. By controlling the relative delay or gain of the signals sent to each loudspeaker, it is possible to recreate a simplified version of the interaural localization cues, the interaural time difference (ITD) and the interaural level difference (ILD) at the two ears. This reproduction of localization cues creates a fictitious sound source whose direction of origin can be freely controlled...