Project Group Hearing, Speech and Audio Technology, Fraunhofer Institute for Digital Media Technology IDMT, Marie-Curie-Str. 2, D-26129 Oldenburg, Germany.
J Acoust Soc Am. 2011 Nov;130(5):2999-3012. doi: 10.1121/1.3641368.
Reverberation usually degrades speech intelligibility for spatially separated speech and noise sources since spatial unmasking is reduced and late reflections decrease the fidelity of the received speech signal. The latter effect could not satisfactorily be predicted by a recently presented binaural speech intelligibility model [Beutelmann et al. (2010). J. Acoust. Soc. Am. 127, 2479-2497]. This study therefore evaluated three extensions of the model to improve its predictions: (1) an extension of the speech intelligibility index based on modulation transfer functions, (2) a correction factor based on the room acoustical quantity "definition," and (3) a separation of the speech signal into useful and detrimental parts. The predictions were compared to results of two experiments in which speech reception thresholds were measured in a reverberant room in quiet and in the presence of a noise source for listeners with normal hearing. All extensions yielded better predictions than the original model when the influence of reverberation was strong, while predictions were similar for conditions with less reverberation. Although model (3) differed substantially in the assumed interaction of binaural processing and early reflections, its predictions were very similar to model (2) that achieved the best fit to the data.
混响通常会降低空间分离的语音和噪声源的语音可懂度，因为空间掩蔽减少，并且后期反射降低了接收到的语音信号的保真度。最近提出的双耳语音可懂度模型[Beutelmann 等人，（2010）。J. Acoust. Soc. Am. 127, 2479-2497]无法令人满意地预测后一种影响。因此，本研究评估了该模型的三个扩展，以改善其预测：（1）基于调制传递函数的语音可懂度指数的扩展，（2）基于房间声学量“定义”的校正因子，以及（3）将语音信号分离为有用和有害部分。预测结果与在安静和存在噪声源的情况下在混响室内测量听力正常的听众的语音接收阈值的两项实验的结果进行了比较。当混响影响较强时，所有扩展均比原始模型的预测更准确，而在混响较小的情况下，预测则相似。尽管模型（3）在双耳处理和早期反射的假定相互作用方面有很大不同，但它的预测与数据拟合最好的模型（2）非常相似。
