Verhey Jesko L, Kollmeier Birger
Medizinische Physik and Gradutiertenkolleg Psychoakustik, Universität Oldenburg, Germany.
J Acoust Soc Am. 2002 Mar;111(3):1349-58. doi: 10.1121/1.1451065.
Loudness was measured as a function of signal bandwidth for 10-, 100-, and 1000-ms-long signals. The test and reference signals were bandpass-filtered noise spectrally centered at 2 kHz. The bandwidth of the test signal was varied from 200 to 6400 Hz. The reference signal had a bandwidth of 3200 Hz. The reference levels were 45, 55, and 65 dB SPL. The level to produce equal loudness was measured with an adaptive, two-interval, two-alternative forced-choice procedure. A loudness matching procedure was used, where the tracks for all signal pairs to be compared were interleaved. Mean results for nine normal-hearing subjects showed that the magnitude of spectral loudness summation depends on signal duration. For all reference levels, a 6- to 8-dB larger level difference between equally loud signals with the smallest (delta f = 200 Hz) and largest (delta f = 6400 Hz) bandwidth is found for 10-ms-long signals than for the 1000-ms-long signals. The duration effect slightly decreases with increasing reference loudness. As a consequence, loudness models should include a duration-dependent compression stage. Alternatively, if a fixed loudness ratio between signals of different duration is assumed, this loudness ratio should depend on the signal spectrum.
针对时长为10毫秒、100毫秒和1000毫秒的信号，测量响度作为信号带宽的函数。测试信号和参考信号均为中心频率在2千赫兹的带通滤波噪声。测试信号的带宽在200赫兹至6400赫兹之间变化。参考信号的带宽为3200赫兹。参考声压级分别为45分贝声压级、55分贝声压级和65分贝声压级。采用自适应双间隔二选一强制选择程序测量产生等响度的声压级。使用响度匹配程序，将所有要比较的信号对的轨迹进行交错排列。九名听力正常受试者的平均结果表明，频谱响度总和的大小取决于信号持续时间。对于所有参考声压级，时长为10毫秒的信号在等响度信号中，最小带宽（Δf = 200赫兹）和最大带宽（Δf = 6400赫兹）之间的声压级差比时长为1000毫秒的信号大6至8分贝。持续时间效应随参考响度的增加而略有降低。因此，响度模型应包括一个与持续时间相关的压缩阶段。或者，如果假设不同持续时间信号之间的响度比固定，那么这个响度比应取决于信号频谱。
