1. A method of sound spatialization with a multichannel encoding and for reproduction on two loudspeakers, comprising a spatial encoding defined by encoding functions associated with a plurality of encoding channels and a decoding by applying filters for reproduction in a binaural context on the two loudspeakers, comprising the steps: a) obtaining an original suite of acoustic transfer functions specific to an individual's morphology, b) fixing spatial encoding functions and/or decoding filters, and c) through successive iterations, optimizing the filters associated with the chosen encoding functions or the encoding functions associated with the chosen filters, or jointly the chosen filters and encoding functions, by minimizing an error calculated as a function of a comparison between: the original suite of transfer functions, and a suite of transfer functions reconstructed on the basis of the encoding functions and the decoding filters, optimized and/or chosen.