Intensity range as a function of task and training

This study examined intensity range as a function of elicitation task (reading and automatic speech sequences), musical training, and the interaction between task and musical training in 31 college students. The results indicated significant differences in loudness range by experiental task. Intensity range for the descending automatic sequence was significantly greater than that for the ascending and reading tasks. While the overall effect of musical training was nonsignificant, there was a significant interaction between task and training, with musicians having a significantly greater mean range on the ascending task. A comparison between ascending and descending tasks indicated a significant mean difference between lower limits and no significant mean difference between upper limits. The range for the reading probe was located approximately in the middle of the total available intensity range.     

A new acoustic perceptual1 model

On the basis of psychological acoustic theories and experiments, this paper proposes an acoustic model which is based on acoustic perceptual feature. Compared with the physiological acoustics based acoustic model, this model is more suitable to represent human’s perceptual features of continuous speech, so it is suitable for recognition of continuous speech.     

Voice source characteristics in six premier country singers

Voice source characteristics as derived from inverse filtering were analyzed in 6 country singers' speech and singing. Results showed that the closed quotient varied systematically with vocal loudness, and that glottal compliance (the ratio between transglottal AC volume displacement and subglottal pressure) decreased with increases in fundamental frequency but remained unaffected by vocal loudness. No striking differences were found in source characteristics between speech and singing within subjects. The degree of phonatory press, as judged by a panel of 19 expert listeners, appeared related to the range in which the singer was singing and to the sound pressure level gain from a doubling of subglottal pressure.     

一种新的听觉感知模型

本文根据心理声学的基本理论和实验资料,提出了一个基于听觉感知特征的听觉模型,与基于生理声学的听觉模型相比较,该模型更能反映人对连续自然语音的感知特性,因而适于对连续语音的识别。     

A-weighted sound pressure level as a loudness/annoyance indicator for environmental sounds - Could it be improved?

A system is introduced with the purpose of showing how an auditory perception system may be built up to include the basic quantities on loudness domain. The quantities are the critical bands, the power law, and the weighting. The power law seems to be the most crucial basis for hypothesizing a loudness function. It has been shown that the power law could be applied as such by assuming the auditory perception system to have two essentially different stimuli: the intensity (sound pressure level) and pure pressure. These physically different quantities seem to be combined in the root of the power law, and in this study the roots are determined from equal-loudness contours. A loudness function is derived on the basis of this finding. By adding the weighting, a method has been constructed for assessing loudness. After defining the weighting, the equal-loudness contours are constructed and are seen to be virtually identical to the contours in ISO 226. It has also been found that the equations for deriving the contours in this standard and in the new ISO 226 may be incorrect, because there is no definition of a sensible loudness function. Finally, it is deduced that the derived weighting must be unequivocal for an auditory perception system (depending solely on the otologically representative group). Finally, the A-weighting (as part of an A-weighted sound pressure level) as such is reasonably similar to the weighting derived in this study. Therefore, this weighting is not the main problem when assessing sounds in respect to loudness. The A-weighting is thus chosen as the weighting for the indicator derived in the study for assessing environmental sounds.     

复杂谐波信号中响度和谱质心的相互影响——响度和谱质心辨别阈的实验研究

根据阈值测量实验和变化一致性测量实验,在单自变量干扰和双自变量干扰两种情况下量化分析响度和谱质心之间的交互关系。研究发现:(1)复杂谐波信号中谱质心对响度的影响强于响度对谱质心的影响;(2)声音的变化方向对被试判断响度和谱质心的阈值存在影响。研究结果进一步呈现了响度和谱质心的定量特征,为听觉属性交互关系的深入研究提供了新的思路。     

一种数字助听器多通道响度补偿方法

该文提出了一种数字助听器非等宽多通道响度补偿方法。该方法研究了完美重构滤波器组分析与综合滤波器的设计方法,并根据人耳对频率的灵敏度特征及对声强的感知特性实现了符合人耳听觉特征的非等宽多通道响度补偿方案。针对典型老年性耳聋患者的实验与仿真结果表明,算法有效补偿了患者缺失的语音高频能量,显著提高了患者的言语辨识率,降低了患者的言语察觉阈。     

基于响度主分量模糊直方图的音频检索方法

根据人耳听觉模型以归一化响度主分量为特征,采用模糊直方图检索音频信息,并根据响度数据的统计分布对直方图编码进行优化。实验结果表明,该方法在低信噪比下具有较好的性能,对噪音具有良好的顽健性(Robustness)。为噪音下的固定音频检索问题提供了有效的解决办法。     

Moore响度计算模型的改进

与早期响度的图表计算方法相比,Moore计算模型是基于解析式的并且实现了响度值随频率、强度改变的连续计算,因此使用起来非常方便;然而,Moore模型计算公式中基本参数值的确定所依据的闻阈标准数据已被修订,并且最新研究表明,Moore模型在确定α值时所做的假设是不合理的;因此本文中(1)提出了利用耳蜗输入输出函数以确定响度函数的方法;(2)根据多个频率处的响度函数重新估计了Moore模型的参数α;(3)根据最新的闻阈标准数据和新的机理重新修订了其它基本参数;(4)利用新的模型重新计算了等响曲线并与原有模型的结果以及最新国际标准进行了对比。结论表明对1～8kHz之间的计算结果有了较大的修订,特别是能很好地预测1～2kHz之间的凸起。