The guqin is the modern name for a plucked seven-string Chinese musical instrument, which literally means "ancient stringed instrument". The guqin has been played since ancient times, is an instrument of great subtlety and refinement. It is sometimes referred to by the Chinese as "the father of Chinese music" or "the instrument of the sages".

Shu or Szechuan Guqin style is one of the oldest and most important Guqin schools. In many ways it is the antithesis of Guangling, emphasizing internal rhythm and vigor instead of a more abstract conception. Yu Bo-Sun adopts a very free approach to rhythm, following the style of xinban, rhythm of the heart. His articulation is precise and free of vibrato.