岷江上游地区小黑水藏族与小姓乡羌族均流传多声部民歌,两者在音乐形态特点、建构方式、生成语境方面既有共同性又有差异性。文章借助现代声音检测软件与记谱分析,得出以下结论:小黑水藏族多声部民歌的特点是小复音、大颤音,小姓乡羌族多声部民歌的特点是大复音、小颤音;两者颤音均是由“音高波动”与“音量波动”的方式建构而成;将两地多声部民歌中的颤音置于“复音”结构中,发现前者的大颤音实则为扩展其处于“挤压”状态的小复音以弱化不和谐音效,后者的小颤音则为填充其处于“宽距”状态的大复音以增加声音厚实感;两地多声部民歌不和谐音效源自生存环境与社会结群层面的现实需求。

In the upper reaches of the Minjiang River, both the Xiaoheishui Tibetans and the Xiaoxing Township Qiang people preserve a form of multi-part folk singing. What are the similarities and differences between their musical characteristics, structural formation, and generative contexts? Using modern sound analysis software and notational transcription, this study draws the following conclusions: Tibetan multi-part folk singing features micro-multiphonics and macro-vibrato, whereas Qiang multi-part folk singing exhibits macro-multiphonics and micro- vibrato. The vibrato in both traditions is formed through a combination of “pitch fluctuation” and “volume fluctuation.” When examining vibrato within the multiphonic structure, it is found that the macro-vibrato in Tibetan singing serves to expand its relatively compressed micro-multiphonics, thereby alleviating dissonant effects. Conversely, the micro-vibrato in Qiang singing fills its more spacious macro-multiphonics to enrich an otherwise hollow sound. The generative context for the dissonant effects in both traditions lies in the communal need that encompasses both survival and social cohesion, manifesting concretely in the production of substantial sonic energy to drive away fierce animals and to strengthen group identity.