Parametric Ambisonic Encoding using a Microphone Array with a One-plus-Three Configuration

Abstract

A parametric signal-dependent method is proposed for the task of encoding a studio omnidirectional microphone signal into the Ambisonics format. This is realised by affixing three additional sensors to the surface of the cylindrical microphone casing; representing a practical solution for imparting spatial audio recording capabilities onto an otherwise non-spatial audio compliant microphone. The one-plus-three configuration and parametric encoding method were evaluated through formal listening tests using simulated sound scenes and array recordings, given a binaural decoding workflow. The results indicate that, when compared to employing first-order signals obtained linearly using an open tetrahedral array, or third-order signals derived from a 19-sensor spherical array, the proposed system is able to produce perceptually closer renderings to those obtained using ideal third-order signals.