Escuela de Ingenierıa en Sonido y Acustica, Universidad de Las Américas, Avenue Granados and Colimes, Quito EC170125, Ecuador.
Department of Psychology, University of Cambridge, Downing Street, Cambridge CB2 3EB, United Kingdom.
J Acoust Soc Am. 2019 Aug;146(2):1142. doi: 10.1121/1.5121700.
Some environmental sounds have strong amplitude fluctuations that may affect their perceived loudness and annoyance. This study assessed the effect of beat rate (f) and center frequency (f) on the loudness of low-frequency beating tones. The loudness of two-tone complexes (TTCs) with f = 40, 63, 80, and 1000 Hz was matched with that of unmodulated tones (UTs). Frequency differences between the TTC components, corresponding to f = 1, 2, 5, and 12 Hz, were used. To compensate for the steep decline in hearing sensitivity below 100 Hz, prior to the loudness match, subjects adjusted the relative levels (ΔL) of the TTC components to give maximum beat perception. Twenty-four normal-hearing subjects were tested. The values of ΔL giving best beats were well predicted from the transfer function of the middle ear and the estimated shapes of the auditory filters, assuming that the auditory filter whose output dominated the beat percept was centered somewhat above f. At the same root-mean-square level and independent of f, TTCs were perceived as louder than UTs for f ≤ 2 Hz, had roughly equal loudness to UTs for f = 5 Hz, and were less loud than UTs for f = 12 Hz.
一些环境声音具有较强的幅度波动，可能会影响其感知的响度和烦扰度。本研究评估了拍频率（f）和中心频率（f）对低频拍频音响度的影响。使用频率差为 1、2、5 和 12 Hz 的两音复合音（TTC）与未调制音（UT）进行响度匹配，TTC 的 f 值分别为 40、63、80 和 1000 Hz。为了补偿 100 Hz 以下听力灵敏度的急剧下降，在进行响度匹配之前，受试者调整 TTC 分量的相对水平（ΔL）以获得最佳拍频感知。对 24 名正常听力受试者进行了测试。假设主导拍频感知的听觉滤波器位于 f 上方的某个位置，从中耳传递函数和估计的听觉滤波器形状可以很好地预测出产生最佳拍频的ΔL 值。在相同的均方根水平下，与 f 无关，当 f ≤ 2 Hz 时，TTC 比 UTs 感知为更响亮，当 f = 5 Hz 时，TTC 与 UTs 的响度大致相等，而当 f = 12 Hz 时，TTC 比 UTs 更不响亮。
