3D soundfield reproduction using non-spherical loudspeaker arrays

Abstract

Three dimensional (3D) spatial soundfield reconstruction techniques typically need multiple loudspeakers placed on the surface of a sphere covering a desired region of reconstruction. Such array geometries have certain limitations that make them impractical in most of the intended applications. In this paper, we show how to reconstruct 3D soundfields using a set of circular arrays. The proposed method uses circular harmonics alongwith the underlying theory of wavefield propagation. Specifically, we use the properties of the associated Legendre functions and the spherical Hankel functions for loudspeaker placement. As an illustration, we design a third order spherical harmonic reconstruction system using 16 loudspeakers.