Qupai

A qupai (; also called ) is the generic term for a fixed melody used in traditional Chinese music. The literal meaning is "named tune," "labeled melody," "titled tune," or "titled song". "Qupai" are relatively brief, most comprising between 20 and 70 measures in 2/4 meter. Many "qupai" are centuries old, but only a few of these have been handed down to the present. 
"Qupai" are commonly used in Chinese opera, such as "kunqu" and Beijing opera, as well as by folk and ritual ensembles, including "Jiangnan sizhu" and Taoist ritual music. "Qupai" have also been used as the basis for 20th century compositions for Chinese instruments, both solo and ensemble. In these contexts these stock melodies very often serve as a basis for melodic elaboration and variation. This variation is particularly well codified in the "taoqu" structure of "Chaozhou xianshi" music.
The "Baisha xiyue" tradition of the Naxi of Lijiang, Yunnan utilizes 24 "qupai".