Sepu 瑟譜 "Notes on" or "Music score for the large zither" is a book on the large zither (se 瑟) written during the Yuan period 元 (1279-1368) by Xiong Penglai 熊朋來 (1254-1323), courtesy name Yuke 與可. He hailed from Yuzang 豫章 (modern Nanchang 南昌, Jiangxi ) and obtained his jinshi degree in 1274, but never obtained an office and instead made a life as a private teacher in the region of Fujian and Luling 廬陵. He was an expert in the seal script as well as in tuning the pitch pipes and composing songs.
Prince Zhu Zaiyu 朱載堉 (1536-c. 1610), author of Yuelü quanshu 樂律全書, also wrote a book on the large se zither with the same title.
The 6-juan long book is concerned with ritual music played for entertainment. It is very interesting because the large se zither had been abandoned for a long time, and instruction in its play was nearly lost. It was only reconstructed during the Song period 宋 (960-1279) particularly to be able to perform "authentic" music for Confucian rituals, especially pieces from the Classic Shijing 詩經 "Book of Songs".
Xiong Penglai therefore wrote a two-parts long rhapsody, Sefu 瑟賦, to revive this instrument. He also collected all ancient statements about the se zither and compiled a book about it. The Sepu consists of eight chapters describing the musical instrument and its history, the melodies that could be played on it, finger techniques, and various information on the art of playing the se zither. The book includes 12 old Tang-period 唐 (618-907) songs (Shi jiupu 詩舊譜) from the Shijing, transmitted by Zhao Yansu 趙彥肅, and 20 own songs (Shi xinpu 詩新譜), as well as some music scores for ritual offerings in the Confucius temple.
In the field of musical theory, the book includes many errors, but it is important as a collection of all available information on this kind of musical instrument.
The Sepu was included in the Ming-period 明 (1368-1644) encyclopaedia Yongle dadian 永樂大典 and is to be found in the series Siku quanshu 四庫全書, Zhihai 指海, Mohai jinhu 墨海金壺, Jingyuan 經苑, Yueyatang congshu 粵雅堂叢書 and Congshu jicheng chubian 叢書集成初編.