The shamisen has three strings and is played with a plectrum. The body of the instrument is a box, made of four pieces of wood and then covered with cat skin or dog skin. Cat skin and dog skin transmit the vibrations of the instrument very sensitively, but are very fragile and split easily. In recent years, combination plastic-cloth skins, which are much easier to care for, have been developed. In some styles, like Nagauta, the instrument is played so that the plectrum strikes the skin over the hollow portion of the instrument, making it as much a percussion instrument as a string instrument. The strings are made of silk and are numbered from the thickest string, so the thickest string, on the top of the instrument is "ichi no ito (first string)", the middle string is "ni no ito (second string)" and the thinnest string, which is used the most, is "san no ito (third string)".
|The strings are (from left to right) ichi no ito, ni no ito, san no ito.
Strings are made of natural silk. The thread from about 10 silkworm cocoons is spun together to make the base thread and then, about 50 of these base threads are spun together to make the san no ito, which means that one san no ito requires over 500 silkworm cocoons. In turn, several san no ito are spun together to make the ni no ito and ichi no ito. These threads are spun together by hand, a traditional method that brings out the quality of the natural fiber with the least damage.
|There are three sizes of neck, futozao, the thickest, used for Gidayu and Tsugaru Jamisen, chuzao, or medium size, used for Tokiwazu and Kiyomoto and hosozao, the narrowest, used for Nagauta. Itchu Bushi uses a medium sized neck, which gives the music a very quiet and solidly balanced sound.
The best wood for the sao is koki, a hardwood imported from the Himalayas, followed by shitan (rosewood) and kashi(oak). The wood for the neck needs to be very hard since it wears down from the players fingernails sliding along it constantly.
|The box for the body is made from four boards of karin or Chinese quince, which is then chiseled and sanded into a rounded shape. The chisel marks inside the box are left, because they help the vibration of air inside the body of the instrument.
The body is covered with cat skin and the red dots are the nipples of the animal. These are important because they show that the skin is centered on the body of the instrument, essential for a good sound.