The sanxian has a dry, somewhat percussive tone and loud volume similar to the banjo. The larger sizes have a of three octaves. It is primarily used as an accompanying instrument, as well as in ensembles and of traditional Chinese instruments, though solo pieces and concertos also exist. Its use in ensembles tends to be analogous to the bass part of continuo. The sanxian is used in ''nanguan'' and ''Jiangnan sizhu'' ensembles, as well as many other folk and classical ensembles.
Traditionally the instrument is plucked with a thin, hard plectrum made from animal horn but today most players use a plastic plectrum or, alternately, their fingernails. This use of fingers to pluck the instrument often shares technique with that of the ''pipa'' and is most commonly used in performance of ''sanxian'' arrangements of works traditionally written for the ''pipa''. This allows for ''pipa'' techniques such as tremolo to be used. Other techniques for ''sanxian'' include the use of harmonics and hitting the skin of the instrument with the plectra or fingernail .
A closely related musical instrument is the Japanese ''shamisen'', which is derived from the ''sanxian'' but which generally uses cat or dog skin rather than snakeskin to cover its resonator. Even more closely related is the Okinawan ''sanshin'', which is also covered in snakeskin. Additionally, the ''sanshin'' and ''sanxian'' share a structurally similar body part consisting of a round-edged square of wood. In the Japanese ''shamisen'', the body is made of four pieces of wood instead of one. The Vietnamese ''&'' is also very similar to the ''sanxian''.
In addition to its use in traditional and classical Chinese music, some popular and rock musicians have used the sanxian, most notably the singer .
Although the ''sanxian'' has historically been one of the most popular Chinese folk instruments , a major decline in the number of sanxian players in classical contexts has been the cause of great concern among enthusiasts of the instrument. As many Chinese orchestras exclude the sanxian, many people are unwilling to learn this instrument. Even in China, very few conservatories offer majors in ''sanxian'', and the small number of students of this instrument, as compared to the ''guzheng'' or ''pipa'', for example, have led to further concerns that the instrument's rich playing traditions may be lost forever. One reason for this is the fact that, unlike the shamisen in Japan, the sanxian lacks an original solo repertoire of its own, with most sanxian solo pieces being arrangements of ''pipa'' melodies, as in the case of "Big Waves Wash Against the Sands". For the most part, use of the sanxian in the Chinese orchestra is as a provider of a de facto bass line. Also, as the neck of the da sanxian is particularly long, there is a great deal of limitation on how virtuosic a sanxian player can be. This is not an issue in the smaller saxian, which are closer in size to the Japanese ''shamisen''.
Like the ''shamisen'', the ''sanxian'' is an instrument particularly susceptible to humidity, although the snake skin used in the ''sanxian'' is somewhat more durable than the membranes of the ''shamisen''. As such, storing the ''sanxian'' in an environment that is less humid can aid in prolonging the life of the snake skin resonator. Many musicians put silica gel in the instrument case to help keep the case from becoming overly humid.
* from The Musical Instruments E-book
* Japan-based Sanxian performer.