Obsolete Korean barrel drum considered to be of Chinese origin. As described in the treatise Akhak kwebŏm (1493), the a was a brightly decorated bulging barrel drum with small heads. It was 146.8 cm long with a circumference in the middle of 64.4 cm and a head diameter of 18.1 cm. The player lifted the instrument with both hands by means of two cloth loops tied to metal rings in the middle of the body and then pounded it against the ground.
The a was used only as part of the mumu (‘military dance’) ensemble and only in ritual music (aak). With the sang (drum) and the ŭng and tok (both idiophones) it was played after the regular sounding of the large drum chin′go, that is after every four-note phrase in the very slow melody.
Sŏng Hyŏn, ed.: Akhak kwebŏm [Guide to the study of music] (Seoul, 1493/...