Janggo, an hourglass-shaped drum, was imported from the West. It is said that it was sent from Song, China, to the country in the 9th year of the reign of King Yejoing of the Goryeo period. It is also called "seyogo" since it has a slender waist. Seyogo comes from the shape and janggo comes from the way of producing the sound. It is struck by a stick, giving it the name of "jang". It is played with the drummer sitting down on the floor. The left head is made of thick hide, producing low sounds, and the right head is made of thin hide, producing high pitches. Janggo is one of the leather percussion instruments consisting of an hour-glass shaped body with two heads (hides or skins) lapped onto metal hoops, 45 cm in diameter, placed over the open ends of the body, and secured by counter-hoops. There are strings between the two heads, and each string is bound with a leather binder, which regulates tones.
The right head is struck by a thin and long bamboo stick and the left head by the palm of a hand. Literally, there is nearly no Korean music in which janggo is not played. It is a very important instrument for rhythms used in all genres of Korean music including gut, pungmul, talchum, and folk songs.
