Journal Article
Open Access
Domains of Practical Applicability for Parametric Interpolation Methods for Virtual Sound Field Navigation
Journal of the Audio Engineering Society · Volume 67 · Issue 11 · pp. 882–893 · November 2019
Abstract
Given an ambisonics-encoded sound field (i.e., a sound field that has been decomposed into spherical harmonics), virtual navigation enables a listener to explore the recorded space and, ideally, experience a spatially- and tonally-accurate perception of the sound field. Suitable domains were established for the practical application of two state-of-the-art parametric interpolation methods for virtual navigation of ambisonics-encoded sound fields. Although several navigational methods have been developed, existing studies rarely include comparisons between methods, and practical assessments of such methods have been limited. The authors conducted numerical simulations in order to characterize and compare the performance of the time-frequency analysis interpolation method of Thiergart et al. to the recently-proposed parametric valid microphone interpolation method. The simulations involved simple incident sound fields consisting of a two-microphone array and a single point-source with varied source distance and azimuth, microphone spacing, and listener position. The errors introduced by the two methods were objectively evaluated in terms of metrics for sound level, spectral coloration, source localization, and diffuseness. Various practical domains were subsequently identified, and guidelines were established with which to choose between these methods based on their intended application.
