Spatial sound field synthesis and upmixing based on the equivalent source method.
Given scarce number of recorded signals, spatial sound field synthesis with an extended sweet spot is a challenging problem in acoustic array signal processing. To address the problem, a synthesis and upmixing approach inspired by the equivalent source method (ESM) is proposed. The synthesis procedure is based on the pressure signals recorded by a microphone array and requires no source model. The array geometry can also be arbitrary. Four upmixing strategies are adopted to enhance the resolution of the reproduced sound field when there are more channels of loudspeakers than the microphones. Multi-channel inverse filtering with regularization is exploited to deal with the ill-posedness in the reconstruction process. The distance between the microphone and loudspeaker arrays is optimized to achieve the best synthesis quality. To validate the proposed system, numerical simulations and subjective listening experiments are performed. The results demonstrated that all upmixing methods improved the quality of reproduced target sound field over the original reproduction. In particular, the underdetermined ESM interpolation method yielded the best spatial sound field synthesis in terms of the reproduction error, timbral quality, and spatial quality.
Department of Power Mechanical Engineering, National Tsing Hua University, Number 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan.
Mingsian R
MR
Bai
Department of Power Mechanical Engineering, National Tsing Hua University, Number 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan.
Hoshen
H
Hsu
Department of Power Mechanical Engineering, National Tsing Hua University, Number 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan.
Jheng-Ciang
JC
Wen
D000161:Acoustic Stimulation; D000162:Acoustics / Q000295:instrumentation; D003198:Computer Simulation; D006801:Humans; D009038:Motion; D009146:Music; D009716:Numerical Analysis, Computer-Assisted; D011312:Pressure; D015203:Reproducibility of Results; D012815:Signal Processing, Computer-Assisted; D013016:Sound; D013017:Sound Localization; D013018:Sound Spectrography; D013997:Time Factors; D014160:Transducers, Pressure