动态听觉定位因素及其在空间声重放的作用

Dynamic auditory localization cue and its role on spatial sound reproduction

听觉定位机理是生理和心理声学的重要研究内容,在空间声技术方面有重要的作用。听觉定位是多因素(如双耳时间差、双耳声级差、个性化谱因素等)协同作用的结果,但各种因素所提供的信息有一定的冗余。听觉侧向定位机理已比较明确,主要是双耳时间差和双耳声级差的作用,特别是低频双耳时间差起主导作用。但前后和垂直定位机理的一些问题有待解决与澄清。虽然目前已确认个性化谱因素和头部转动带来的动态听觉定位因素提供了前后和垂直定位的信息,并且自从1940年Wallach提出了动态因素的经典假设以来,一直有不少实验从各方面证实了动态因素对听觉定位的作用;但总体上,动态因素的作用特别是对垂直定位的作用常常被低估,甚至较普遍地认为个性化谱因素起了完全主导的作用。听觉定位机理作为空间声技术的心理声学基础,如果假设前提不正确,将无法解析一些重要的实验事实,也无法解决一些普遍存在的问题。目前空间声技术面临的许多问题和误区多数都和动态因素密切相关。文章综述了有关动态听觉定位因素的研究与发展,特别是近年国际上和作者课题组的系列工作,并将其用于分析和解决空间声重放(包括双耳重放、多通路三维空间声和Ambisonics)的一些重要的共性问题,文中最后讨论了存在问题与研究前景。

The mechanism of auditory localization is an important topic on psychoacoustics and physiological acoustics.It also plays a vital role on spatial sound technique.Auditory localization is the consequence of cooperation of multiple cues,but the information provided by various cues is somewhat redundant.The mechanism of lateral localization is relatively clear.Both interaural time difference and interaural level difference contribute to lateral localization,especially the former at low frequency is dominant.In contrast,some problems on the mechanism of front-back and vertical localization should be addressed and clarified.It is already known that both individualized spectral cue and dynamic cue caused by head turning provide information for front-back and vertical localization.Since Wallach proposed the classical hypothesis in 1940,there have been a series of experiment that validated the effect of dynamic cue.However,the contribution of dynamic cue,especially the contribution to vertical localization,is often underestimated,and the spectral cue is generally regarded as the dominant one.The mechanism of auditory localization is essential to spatial sound technique.However,based on inappropriate psychoacoustic hypothesis,it is impossible to explain some important experimental results and solve some general problems,resulting in misunderstanding in the development of spatial sound technique.Recently,many problems in spatial sound technique are closely related to dynamic cue.In this article,the researches and recent progresses on dynamic auditory localization cues,especially a series of related works by international and the author’s groups,are reviewed.The mechanism of dynamic auditory localization cue is applied to address some general problems and clarify the misunderstanding on spatial sound,including Ambisonics,multichannel sound and virtual auditory display.Some problems to be solved and prospects are also discussed.