Crosstalk cancellation in virtual acoustic imaging systems for multiple listeners

The perception of a virtual sound source is achieved by ensuring that the sound pressures at the ears of the listener are equivalent to those produced by the source at the virtual position. Theoretically, with only two loudspeakers for a single listener, virtual sources positioned anywhere in space can be presented provided that “crosstalk cancellation” can be achieved. The crosstalk cancellation problem is central to the problem of sound reproduction since an efficient crosstalk canceller gives one complete control over the sound field at a number of target positions. However, all crosstalk cancellation systems implemented so far have in practice produced virtual sources for only a single listener at a time. The design of crosstalk cancellers for multiple listeners involves a detailed study of the relative orientation of both sources and listeners. It is vital in any multiple listener system to first establish the conditioning of the potential geometrical arrangements of transducers and listeners by using simple free field models of the electro-acoustic transfer functions between transducers and ears. This gives an important link between the conditioning of the electro-acoustic transfer function matrix and the inverse filters for crosstalk cancellation. Optimal transducer arrangements for the efficient crosstalk canceller have been identified for the case of two listeners and these are evaluated here with time domain simulations.