Nábĕlek A K, Letowski T R, Tucker F M
Department of Audiology and Speech Pathology, University of Tennessee, Knoxville 37996-0740.
J Acoust Soc Am. 1989 Oct;86(4):1259-65. doi: 10.1121/1.398740.
Two effects of reverberation on the identification of consonants were evaluated for ten normal-hearing subjects: (1) the overlap of energy of a preceding consonant on the following consonant, called "overlap-masking"; and (2) the internal temporal smearing of energy within each consonant, called "self-masking." The stimuli were eight consonants/p,t,k,f,m,n,l,w/. The consonants were spoken in /s-at/context (experiment 1) and generated by a speech synthesizer in /s-at/ and/-at/contexts (experiment 2). In both experiments, identification of consonants was tested in four conditions: (1) quiet, without degradations; (2) with a babble of voices; (3) with noise that was shaped like either natural or synthetic/s/ for the two experiments, respectively; and (4) with room reverberation. The results for the natural and synthetic syllables indicated that the effect of reverberation on identification of consonants following/s/ was not comparable to masking by either the /s/ -spectrum-shaped noise or the babble. In addition, the results for the synthetic syllables indicated that most of the errors in reverberation for the /s-at/context were similar to a sum of errors in two conditions: (1) with /s/-shaped noise causing overlap masking; and (2) with reverberation causing self-masking within each consonant.
针对10名听力正常的受试者,评估了混响对辅音识别的两种影响:(1)前一个辅音的能量与后一个辅音的能量重叠,称为“重叠掩蔽”;(2)每个辅音内部能量的时间弥散,称为“自掩蔽”。刺激音为8个辅音/p、t、k、f、m、n、l、w/。这些辅音在/s-at/语境中说出(实验1),并由语音合成器在/s-at/和/-at/语境中生成(实验2)。在两个实验中,辅音识别在四种条件下进行测试:(1)安静,无退化;(2)有嘈杂的人声;(3)分别在两个实验中,有形状类似于自然或合成/s/的噪声;(4)有房间混响。自然音节和合成音节的结果表明,混响对/s/后辅音识别的影响与/s/频谱形状噪声或嘈杂人声的掩蔽作用不可比。此外,合成音节的结果表明,/s-at/语境中混响的大多数错误类似于两种条件下错误的总和:(1)/s/形状噪声导致重叠掩蔽;(2)混响导致每个辅音内部自掩蔽。