Abstract：
Purpose: In overtone singing a singer produces two pitches simultaneously, a low-pitched, continuous drone plus a melody played on the higher, flutelike and strongly enhanced overtones of the drone. The purpose of this study was to analyse underlying acoustical, phonatory and articulatory phenomena.Methods: The voice source was analyzed by inverse filtering the sound, the articulation from a dynamic MRI video of the vocal tract profile, and the lip opening from a frontal-view video recording. Vocal tract cross-distances were measured in the MR recording and converted to area functions, the formant frequencies of which computed.Results: Inverse filtering revealed that the overtone enhancement resulted from a close clustering of formants 2 and 3. The MRI material showed that for low enhanced overtone frequencies (FE) the tongue tip was raised and strongly retracted, while for high FE the tongue tip was less retracted but forming a longer constriction. Thus, the tongue configuration changed from an apical/anterior to a dorsal/posterior articulation. The formant frequencies derived from the area functions matched almost perfectly those used for the inverse filtering. Further, analyses of the area functions revealed that the second formant frequency was strongly dependent on the back cavity, and the third on the front cavity, which acted like a Helmholtz resonator, tuned by the tongue tip position and lip opening.Conclusions: This type of overtone singing can be fully explained by the well-established source-filter theory of voice production, as recently found by Bergevin et al. [1] for another type of overtone singing.
摘要：
目的：在泛音演唱中，歌手同时产生两个音高，一个低调的，连续的无人机加上更高的旋律，无人机的翼状和强烈增强的色彩。这项研究的目的是分析潜在的声学，发声和发音现象。方法:通过对声音进行逆滤波分析,声带轮廓的动态MRI视频中的关节，和正面视频记录的嘴唇开口。在MR记录中测量声带交叉距离并转换为区域功能，计算的共振峰频率。结果：逆滤波显示泛音增强是由共振峰2和3的紧密聚类引起的。MRI材料显示，对于低增强泛音频率（FE），舌尖升高并强烈缩回，而对于高FE，舌尖收缩较少，但形成较长的收缩。因此，舌头的构型从根尖/前关节变为背/后关节。从面积函数得出的共振峰频率几乎与用于逆滤波的共振峰频率完全匹配。Further,面积函数的分析表明，第二共振峰频率强烈依赖于背腔，第三个在前腔，它的作用就像一个Helmholtz共振器，通过舌尖的位置和嘴唇的开口调整。结论：这种类型的泛音演唱可以通过完善的音源过滤理论得到充分解释。正如Bergevin等人最近发现的那样。[1]为另一种泛音演唱。
