Beattie R C, Himes B E
J Aud Res. 1984 Jul;24(3):213-29.
The effect of S/N from +20 to -10 db on loudness levels of connected discourse with or without background cafeteria noise was investigated for one set of instructions sampling the most comfortable loudness level (MCLL) and a second set sampling the upper limit of CLL. Normal young adults (N:16) showed no significant differences for either set of instructions in quiet or from 20 to 0 db S/N but mn MCLL was about 5 db lower at -10 db. Elderly hearing-aid wearers (N:10, mn age: 77 yrs) yielded mn differences across S/N of less than 5 db for either set of instructions. No data indicate that the speech CLL accurately predicts optimal hearing-aid gain, while the literature indicates that occasionally the desired maximum intelligibility frequently is not obtained at the MCLL. We question whether MCLL for speech justifies its measurement. A discussion is presented of the Comfort Level Method of adjusting gain in hearing-aid evaluations and a perhaps preferable Threshold Level Method in which the test stimulus is presented at a level corresponding to the predicted threshold and the aid's volume control is adjusted until S just perceives the signal.
研究了信噪比从+20分贝到-10分贝时，有无自助餐厅背景噪音情况下，一组指令采样最舒适响度水平（MCLL）和另一组采样舒适响度水平（CLL）上限时，连贯话语响度水平的变化。正常年轻成年人（N = 16）在安静环境或信噪比从20分贝到0分贝时，两组指令下均无显著差异，但在-10分贝时，MCLL约低5分贝。老年助听器佩戴者（N = 10，平均年龄：77岁）在两组指令下，信噪比变化时的平均差异均小于5分贝。没有数据表明言语CLL能准确预测最佳助听器增益，而文献表明，在MCLL时偶尔无法获得期望的最大可懂度。我们质疑言语MCLL是否值得测量。本文讨论了助听器评估中调整增益的舒适水平法，以及一种可能更优的阈值水平法，即在该方法中，测试刺激以对应预测阈值的水平呈现，然后调整助听器的音量控制，直到受试者刚好能感知到信号。
