The sanshin (, literally "three strings") is an Okinawan musical instrument and precursor of the mainland Japanese (and Amami Islands) shamisen ( ). Often likened to a banjo, it consists of a snakeskin-covered body, neck and three strings.
Its close resemblance in both appearance and name to the Chinese sanxian suggests Chinese origins, the then Ry?ky? Kingdom (pre-Japanese Okinawa) having very close ties with Imperial China. In the 16th century, the sanshin reached the Japanese trading port at Sakai in Osaka, Japan. In mainland Japan, it evolved into the larger shamisen, and many people refer to the sanshin as jabisen (, literally "snake-skin strings") or jamisen (, "snake three strings") due to its snakeskin covering.
Traditionally, it was covered with the skin of the Burmese python, but today, due to CITES regulations, the skin of the python reticulatus is also used. Python skin is used for the skin of the body of the instrument, in contrast to the cat or dogskin used traditionally on Japanese shamisen. Though Okinawa is famous for the venomous habu viper, the habu is in fact too small for its skin to be used to make sanshin, and it is believed that the snakeskin for sanshin has always been imported from Southeast Asia.
Though the pythons used to make sanshin skins today are not an endangered species, the difficulty of distinguishing one snakeskin from another makes transporting real-skin (J: hongawa) sanshin internationally somewhat risky. Due to international wildlife protection treaties, it is not legal to export snakeskin-covered sanshins to some countries (such as the United Kingdom and United States). There is some room for interpretation of this in that the treaties specify that the restriction is for endangered species of snake.
Traditionally, players wear a plectrum, made of a material such as the water buffalo horn, on the index finger. Today, some use a guitar pick or the nail of the index finger. In Amami, long, narrow bamboo plectra are also used, which allow a higher-pitched tone than that of the Okinawa sanshin.
A bamboo bridge raises the strings off the skin, which are white, except in Amami, where they are yellower and thinner. The traditional names for the strings are (from thick to thin) uujiru (, "male string"), nakajiru (, "middle string"), and miijiru (, "female string"). The sanshin has five tunings called chindami (?):
Sheet music for the sanshin is written in a unique transcription system called kunkunshi (Okinawan: pronounced [ku?kunshi:]). It is named for the first three notes of Chinese melody that was widely known during its development. Its creator is believed to be Mongaku Terukina or his student Choki Yakabi ( Yakabi Ch?ki) in the early to mid-1700s. A set of kanji are used to represent specific finger positions. Unlike European musical notation, kunkunshi can only be interpreted specifically through the sanshin.