Source-Location-Informed Sound Field Recording and Reproduction

Abstract

A sound field recording and reproduction method that exploits prior information on the locations of sound sources to be reproduced is proposed. Current methods do not take such prior information into consideration in the transformation from the signals received by microphones into the driving signals of loudspeakers. The proposed method for planar and linear arrays of microphones and loudspeakers optimizes spatial basis functions and their coefficients, which represent the driving signals of loudspeakers, on the basis of the maximum a posteriori (MAP) estimation approach, leading to higher reproduction accuracy above the spatial Nyquist frequency when there are fewer microphones than loudspeakers, i.e., super-resolution in sound field recording and reproduction. Numerical simulations show that the reproduction accuracy at frequencies above the spatial Nyquist frequency was maintained using the proposed method even when there was a mismatch between actual and prior locations of the sound sources to be reproduced.