Geometry Sensitivity in Low-Count Virtual Microphone Arrays: From Tetrahedral Baselines to Stochastic Spherical Layouts

de Brit B, Dorran D. Geometry Sensitivity in Low-Count Virtual Microphone Arrays: From Tetrahedral Baselines to Stochastic Spherical Layouts. In: Express Paper. Audio Engineering Society; 2026. Paper 444. Available from: https://aes.org/publications/elibrary-page/?id=23263

@inproceedings{deBrit2026_23263,
  author = {de Brit, Brian and Dorran, David},
  title = {{Geometry Sensitivity in Low-Count Virtual Microphone Arrays: From Tetrahedral Baselines to Stochastic Spherical Layouts}},
  note = {Paper 444},
  year = {2026},
  month = may,
  publisher = {Audio Engineering Society},
  url = {https://aes.org/publications/elibrary-page/?id=23263}
}

TY  - CPAPER
TI  - Geometry Sensitivity in Low-Count Virtual Microphone Arrays: From Tetrahedral Baselines to Stochastic Spherical Layouts
AU  - de Brit, Brian
AU  - Dorran, David
M1  - Paper 444
PY  - 2026
DA  - 2026/05/28
UR  - https://aes.org/publications/elibrary-page/?id=23263
PB  - Audio Engineering Society
LA  - en
AB  - Virtual Microphone Array (VMA) techniques are being investigated to support room-acoustics optimisation in live sound environments. Earlier work by these authors found that a compact four-microphone regular tetrahedral array performed strongly relative to its low sensor count. More recent work in virtual sensing and the Remote Microphone Technique has treated microphone array geometry as an explicit design variable. These studies indicate that remote estimation performance depends on array geometry, and that conventional array geometries are not always the strongest performers. This paper focuses on the four-microphone non-coplanar case, where only a small number of practical regular geometries are typically considered. Monte Carlo simulation is used to explore an ensemble of stochastically generated spherical four-microphone layouts at equal array aperture. Their performance is compared against regular tetrahedral and triangular-pyramid (3+1) four-microphone baselines. A consistent evaluation protocol is applied across multiple listener-region offsets and standard beamforming estimators. A targeted follow-up study further showed that orientation can strongly affect the relative performance of compact four-microphone layouts. The results therefore support the view that both geometry and orientation are key design parameters in low-count VMAs.
ER  -