Nagak

The nagak is a wind-instrument made from a large seashell and played as a horn in Korean traditional music. It produces only a single tone and is used primarily in the military procession music called daechwita. The mouthpiece of the nagak is made by making a hole in the pointed end of the conch, into which a mouthpiece is fitted. This instrument is first recorded as being used in Goryeo.

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