A method for reproducing binaural audio over an array of loudspeakers is presented. The proposed method is based on spatially-matched filters and is shown to be, in general, more stable than the conventional inverse filter approach. The non-weighted formulation of the method introduces reductions in the reproduced pressure magnitude response at each control point and is therefore inherently lossy. On the other hand, far less error is introduced for frequencies where the Hermitian angle between the row vectors of the plant matrix is close to ninety degrees. For sufficiently dense arrays, little error is introduced at mid-low and high frequencies. The trade-off between reductions in the reproduced target signals and crosstalk cancellation is controlled by introducing frequency-dependent weights to the left and right channel filters. The weights that minimise the error are derived. It is shown that the optimal weight solution emphasises achieved crosstalk cancellation over lossless focusing.

The low frequency behaviour of the source strength solution of the two loudspeaker crosstalk cancellation system is analysed. Using the rigid sphere head model, an accurate 1storder approximation of the source strength solution is derived, assuming a centred listener position. It is shown that the 1storder approximation of the source strength solution corresponds to the well-known stereo sine law. The validity of this approximation for real systems is supported by a comparison of simulated low frequency complex source strengths and the real stereo panning functions. To obtain a realistic analysis, the simulated source strengths are created using KEMAR head-related transfer functions. It is shown that the simulated source strengths converge to the stereo sine law in the low frequency limit under the expected conditions.