Key Laboratory of Speech Acoustics and Content Understanding, Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190, China.
University of Chinese Academy of Sciences, Beijing 100049, China.
J Acoust Soc Am. 2024 May 1;155(5):2934-2947. doi: 10.1121/10.0025857.
Spatial separation and fundamental frequency (F0) separation are effective cues for improving the intelligibility of target speech in multi-talker scenarios. Previous studies predominantly focused on spatial configurations within the frontal hemifield, overlooking the ipsilateral side and the entire median plane, where localization confusion often occurs. This study investigated the impact of spatial and F0 separation on intelligibility under the above-mentioned underexplored spatial configurations. The speech reception thresholds were measured through three experiments for scenarios involving two to four talkers, either in the ipsilateral horizontal plane or in the entire median plane, utilizing monotonized speech with varying F0s as stimuli. The results revealed that spatial separation in symmetrical positions (front-back symmetry in the ipsilateral horizontal plane or front-back, up-down symmetry in the median plane) contributes positively to intelligibility. Both target direction and relative target-masker separation influence the masking release attributed to spatial separation. As the number of talkers exceeds two, the masking release from spatial separation diminishes. Nevertheless, F0 separation remains as a remarkably effective cue and could even facilitate spatial separation in improving intelligibility. Further analysis indicated that current intelligibility models encounter difficulties in accurately predicting intelligibility in scenarios explored in this study.
空间分离和基频（F0）分离是提高多说话人场景中目标语音可懂度的有效线索。先前的研究主要集中在前半球面内的空间配置，忽略了同侧和整个正中面，而这些区域经常会出现定位混淆。本研究探讨了在上述未充分探索的空间配置下，空间和 F0 分离对可懂度的影响。通过三个实验测量了涉及两个到四个说话者的场景的语音接收阈值，这些实验分别在同侧水平平面或整个正中面内进行，使用具有不同 F0 的单调语音作为刺激。结果表明，对称位置的空间分离（同侧水平平面中的前后对称或正中面中的前后、上下对称）对可懂度有积极影响。目标方向和相对目标-掩蔽者分离都会影响归因于空间分离的掩蔽释放。随着说话者数量超过两个，空间分离的掩蔽释放会减少。然而，F0 分离仍然是一个非常有效的线索，甚至可以促进空间分离以提高可懂度。进一步的分析表明，当前的可懂度模型在准确预测本研究中探索的场景的可懂度方面存在困难。
