Perceptual evaluation of a new, portable three-dimensional recording technique: “W-Ambisonics”

Abstract

In order to exploit strengths and avoid weaknesses of the First Order Ambisonics (FOA) microphone technique, we devised a new, portable 3D microphone recording technique, “W-Ambisonics.” This new technique incorporates a spaced stereo cardioid microphone pair (for frontal information) with two FOA microphone arrays (for lateral, rear, and height information). In W-Ambisonics, two FOA microphones are spaced 17 cm apart to capture and represent interaural cues precisely, with two cardioid microphones spaced 50 cm apart, 50 cm in front, which improves frontal directionality. Combining these two microphone pairs enables the translation of recorded audio into various reproduction formats according to practical limitations in reproduction peripherals. The design focus of this technique was efficiency in the recording stage and scalability in the reproduction stage. We conducted three perceptual experiments whose results show that the W-Ambisonics method enables improved lateral localization, provides comparable sound quality to the conventional spaced array technique, and translates spacious yet precise sound images in listening evaluations of a binauralized headphone rendering. The W-Ambisonics microphone technique is practical, precise, and scalable across multiple reproduction scenarios, from binaural to multichannel systems.