There are three types of Gayageum, which can be roughly divided into three types: "Jongnak Gayagum" (ancient Gayagum), "Sandyo Gayagum", and modern "21-string Gayagum".
Guqin
The groove of the qin is made of single wood tung, without a bottom plate, with a sheep ear-shaped device at the end, with twelve strings (using silk strings of varying thickness) and twelve strings (herringbone-shaped goose columns) . Such Gayageum was rare by the beginning of the twentieth century.
San tune
It belongs to the modern Gayageum, which has been greatly improved in shape, such as removing the shorn wood at the end, adding chestnut water to the body, dyed tail, and thirteen strings (silk strings). Mainly used for scattered music.
21 string piano
It is an improved Gayageum for modern use. In shape, remove the dyed tail at the end. There are 21 strings. There are two kinds of strings: nylon strings and metal steel wire-wound nylon strings; there are two kinds of tuning methods: the 7-tone scale tuning method and the pentatonic scale tuning method.