Spatial Quality Measure for Mixed-phase Impulse Response Equalization

Bharitkar S, Decanio W. Spatial Quality Measure for Mixed-phase Impulse Response Equalization. In: Convention Paper. Audio Engineering Society; 2026. Paper 10258. Available from: https://aes.org/publications/elibrary-page/?id=23206

@inproceedings{Bharitkar2026_23206,
  author = {Bharitkar, Sunil and Decanio, William},
  title = {{Spatial Quality Measure for Mixed-phase Impulse Response Equalization}},
  note = {Paper 10258},
  year = {2026},
  month = may,
  publisher = {Audio Engineering Society},
  url = {https://aes.org/publications/elibrary-page/?id=23206}
}

TY  - CPAPER
TI  - Spatial Quality Measure for Mixed-phase Impulse Response Equalization
AU  - Bharitkar, Sunil
AU  - Decanio, William
M1  - Paper 10258
PY  - 2026
DA  - 2026/05/28
UR  - https://aes.org/publications/elibrary-page/?id=23206
PB  - Audio Engineering Society
LA  - en
AB  - Mixed-phase impulse response equalization can improve magnitude and phase response, but conventional objectives such as mean-squared error (MSE) can favor solutions that introduce objectionable temporal artifacts, including pre-echo and extended post-echo ringing. This paper proposes a Spatial Equalization Quality Measure (SEQM) to select a mixed-phase equalization filter that better controls these artifacts while remaining computationally simple and applicable across multiple listening positions. SEQM combines (i) a temporal-domain metric that penalizes energy preceding the main pulse of an impulse response and energy persisting after it, while also accounting for the decay rate of the post-response tail, with (ii) a spatial aggregation rule that summarizes quality across measurement positions. We use SEQM to select the modeling delay for mixed-phase finite-impulse-response (FIR) equalization and to compare mixed-phase FIR designs with minimum-phase FIR and IIR alternatives under a common multi-position measurement framework. Experiments using semi-anechoic measurements across 34 spatial positions for two loudspeakers show that SEQM consistently selects substantially shorter delays than MSE-based selection and yields impulse responses with reduced pre-echo and faster post-response decay, while maintaining comparable frequency-response equalization. These results suggest that SEQM is a practical objective tool for designing multi-position mixed-phase equalization filters.
ER  -