Akhak Gwebeom, the first illustrated treatise on court music and dances compiled in 1493 during the reign of King Seongjong, was created by court officials including Seong Hyeon, Yu Ja-gwang and Sin Mal-pyeong, who had profound knowledge of music.
Chapter 1 of Akhak Gwebeom presents theories on music, including the twelve pitches and modes that serve as the standard for the pitches of traditional Korean music.