佛祖統紀 35.57

35.57

六年。陳思王曹植（文帝弟字子建）每讀佛經。輒留連嗟翫以為至道之宗極。甞遊漁山聞空中梵天之響。乃摹其聲節寫為梵唄（音敗此云讚歎）撰文制音凡六契（經音義云猶一節也）傳為後式。

In the sixth year, Prince Si of Chen, Cao Zhi (Emperor Wen's younger brother, courtesy name Zijian), whenever he read Buddhist scriptures, would always linger over them in admiration and pleasure, regarding them as the ultimate consummation of the Supreme Way. Once, while roaming Mount Yu, he heard the sounds of the Brahma-heavens in the air; he then imitated their tones and cadences and recorded them as Sanskrit chanting (fanbai; 'bai' is pronounced like bai [敗], and means 'praise'). He composed the texts and arranged the tunes, totaling six stanzas (the Jingyin yi states this is like a section), which were handed down as a model for later generations.