Yang W, Bradley J S
National Research Council, Montreal Road, Ottawa, Canada.
J Acoust Soc Am. 2009 Feb;125(2):922-33. doi: 10.1121/1.3058900.
This paper reports new measurements of the intelligibility of speech in conditions representative of elementary school classrooms. The speech test material was binaurally recorded in simulated classroom conditions and played back to subjects over headphones. Subjects included grade 1, 3, and 6 students (6, 8, and 11 year olds) as well as adults. Recognizing that reverberation time is not a complete descriptor of room acoustics conditions, simulated conditions included realistic early-to-late arriving sound ratios as well as varied reverberation time. For conditions of constant signal-to-noise ratio, intelligibility scores increased with decreasing reverberation time. However, for conditions including realistic increases in speech level with varied reverberation time for constant noise level, intelligibility scores were near maximum for a range of reverberation times. Young children's intelligibility scores benefited from added early reflections of speech sounds similar to adult listeners. The effect of varied reverberation time on the intelligibility of speech for young children was much less than the effect of varied signal-to-noise ratio. The results can be used to help to determine ideal conditions for speech communication in classrooms for younger listeners.
本文报告了在代表小学教室环境的条件下对语音可懂度的新测量结果。语音测试材料是在模拟教室条件下进行双耳录制的，并通过耳机播放给受试者。受试者包括一年级、三年级和六年级的学生（6岁、8岁和11岁）以及成年人。认识到混响时间并非房间声学条件的完整描述指标，模拟条件包括逼真的早到晚到声音比例以及不同的混响时间。在信噪比恒定的条件下，可懂度得分随混响时间的减少而增加。然而，对于在恒定噪声水平下随着混响时间变化语音电平实际增加的条件，在一系列混响时间内可懂度得分接近最大值。幼儿的可懂度得分受益于类似于成年听众的语音早期反射增加。混响时间变化对幼儿语音可懂度的影响远小于信噪比变化的影响。这些结果可用于帮助确定针对较年轻听众的教室语音通信的理想条件。
