Korean music called Chong-ak has two styles - aak performed in palaces and min-gan chong-ak performed outside. An example of Chong-ak is Sujech-on, an instrumental composition. Some traditional Korean musical instruments include the changgo hourglass-shaped drum, haegum zither played with a bow, komingo small koto-like instrument, kayagum 12-string zither, and ching large gong struck with a wrapped mallet.