Acoustics Laboratory, Department of Signal Processing and Acoustics, Aalto University, Espoo, 02150, Finland.
Division of Applied Acoustics, Chalmers University of Technology, Gothenburg, 412 96, Sweden.
J Acoust Soc Am. 2022 Oct;152(4):2266. doi: 10.1121/10.0014830.
Room acoustic simulations using the finite-difference time-domain method on a wide frequency range can be computationally expensive and typically contain numerical dispersion. Numerical dispersion can be audible and, thus, constitutes an artifact in auralizations. There is a need to measure perceptual thresholds for numerical dispersion to achieve an optimal balance between computational complexity and audibility of dispersion. This work measures the perceptual detection thresholds for numerical dispersion in binaural auralizations of two acoustically different rooms. Numerical dispersion is incorporated into measured binaural room impulse responses (BRIRs) by the means of filters that represent the dispersion that plane waves experience, which propagate in the simulation in the direction of the worst-case dispersion error. The results show that the perceptual detection threshold is generally lower for the most reverberant room and greatly depends on the source signal independently of the room in which the threshold is measured. It is the most noticeable in the pure BRIRs, i.e., with an impulse as source signal, and almost unnoticeable with speech. The results also show that there was no statistical evidence that the perceptual thresholds for the conditions where numerical dispersion was present or absent in the direct path of the BRIRs be different.
在较宽的频率范围内使用时域有限差分法进行房间声学模拟可能计算成本很高，并且通常包含数值色散。数值色散可能听得见，因此在听觉化中构成了一种伪像。需要测量数值色散的感知阈值，以在计算复杂性和色散可听度之间达到最佳平衡。这项工作测量了两种声学上不同的房间的双耳听觉化中数值色散的感知检测阈值。通过滤波器将数值色散纳入测量的双耳房间脉冲响应（BRIR）中，滤波器表示平面波在模拟中传播的方向上经历的色散，该方向是最坏情况下的色散误差。结果表明，对于最混响的房间，感知检测阈值通常较低，并且独立于测量阈值的房间，很大程度上取决于源信号。在纯 BRIR 中最为明显，即使用脉冲作为源信号，而使用语音时几乎察觉不到。结果还表明，没有统计证据表明 BRIR 中直接路径存在或不存在数值色散条件下的感知阈值不同。
