Sor Khao Khwai
The Sor Khao Khwai (in Thai ซอ เขา ควาย ) belongs to the group of string instruments and is played in the south of Isan , the northeast region of Thailand .
The instrument consists of a sound body , a slightly curved fingerboard and is played with metal strings. The sound body is made from the horn of water buffalo , the head is covered with snakeskin .
The Sor Gradong Tao is used as a solo instrument or played together with the So Khantruem in an ensemble , mostly as an accompaniment to folk dances at festivals.