The Moon Reflected in Er-quen, Ah-Bing‘s original creation transcribed by Yang Yin-liu in 1950, has been greatly praised. The advent of this musical composition made successors pass on this folk musician’s performing art and the composing features, leading to the existence of a new-born instrument, Er-quen, which was jointly developed by Wang Guo-Tung and Man Ruey-Hsing and perfectly fit to Ah-Bing’s works.Wang Yue-Ming commissioned a musical composition by Singapore Chinese Orchestra who designated Tenor Erhu as the solo, accomplished her first concerto grosso-Fantasia of Western Regions- as expected in 2007. The research. What exactly the historical context of instruments is and how come they haven’t been well-developed are the motivations of this research. The Moon Reflected In Er-quen and Fantasia of Western Regions are the main theme in this research, both of which are typical works. We will learn the contribution of both through combing out the history and the reformation process of instruments and synthesizing composers’ lifetimes and creating courses. In the process of collecting information, we discovered this commonly-called Tenor Erhu possesses several appellations, such as Er-quen, Low-tune Erhu, Low-tune and thick-stringed Erhu, and Di-Diao-Men Erhu. This research aims at synthesizing the historical process of instrument development and thus the author employees Tenor Erhu so as to the convenience of writing. The study shows that Yan transcribed The Moon Reflected In Er-quen created by Ah-Bing, managed to its wide-spread and passed on to successors, while this instrument is not completed expanded. Also, there hasn’t been any other musical composition featuring Tenor Erhu after Fantasia of Western Regions in terms of creating quantity. We expect this study can inspire composers to put more endeavor to create musical instruments featuring Tenor Erhu.
