The dihu is a large bowed string instrument from China. It has a large soundbox covered on one end with snakeskin. Like most other members of the huqin family of instruments, it has two strings and is held vertically. The instrument's name derives from "dī," meaning "low," and "hú" .
The instrument comes in three sizes:
*The ''xiaodihu'' , pitched one octave below the ''erhu'' . It is the tenor member of the erhu family .
*The ''zhongdihu'', pitched one octave below the zhonghu . It is the bass member of the erhu family.
*The ''dadihu'', pitched one octave below the ''xiaodihu'' and two octaves below the erhu . It is the contrabass member of the erhu family.
The ''dihu'' family was developed for orchestral use in the 1930s as lower members of the ''erhu'' family , but by the late 20th century it had largely fallen into disuse. Part of the reason for this is that it is unwieldy to play. Also, the fact that the bow passes between the instrument's two strings means that playing pizzicato is difficult; thus, the larger four-string gehu and diyingehu are generally used in Chinese orchestras for the lower bowed string voices instead.