The eight categories of Chinese musical instruments are: silk, bamboo, wood, stone, metal, clay, gourd and hide. There are other instruments which may not fit these classifications.

Xun is one of the traditional Chinese musical instruments. The xun (埙) is a globular, flute-like, Chinese musical instrument. The xun was initially made of stone or bone, and later of clay or ceramic. It is similar to an ocarina but without a fipple mouthpiece. Other Chinese flute-like instruments, such as the Wudu and Taodi, however, include a fipple.

The xun is made in several egg-shaped sizes, and is one of the oldest Chinese instruments. It has a blowing hole on top and generally eight smaller finger holes (three each for the index, middle, and ring fingers of each hand, and one for each thumb).

The Korean equivalent is the hun. In Japan, the same type of instrument is called tsuchibue (hiragana: つちぶえ ; kanji: 土笛, lit. "earthen flute").