Localisation of elevated virtual sources in higher order Ambisonic soundfields

Abstract

Ambisonics allows the reproduction of 3D sound-fields. Higher-order Ambisonics provides improved resolution, and the promise of enhanced localisation at the expense of higher channel counts, and increased broadcast bandwidth, and storage requirements. Due to the resolution of human hearing it is possible that lower-order reproduction is sufficient for the vertical plane, resulting in mixed-order Ambisonic renderings. To investigate, we report the results of subjective localisation tests for virtual sources placed in the vertical plane at different elevations and azimuths, for 1st, 2 nd and 3rd order Ambisonic reproduction over a 16 loudspeaker system. The results provide insights into the requirements of higher-order Ambisonics for broadcast and domestic reproduction.