Kokyu is the only Japanese traditional
bowed string instrument. It is vertically set up on knees, having
three strings tuned in D-G-C (perfect 4th upward), or D-G-D (an
octave, consisting of perfect 4th and 5th) as a standard setting,
and do not have fret on the fingerboard.
Due to the size of its body as a resonator that is a little smaller
than shamisen's and the tension of strings, its volume (sound
level) is rather small(weak), comparing to shamisen's which usually
played by a plectrum and its timbrel character sounds percussive.
If Kokyu is played with an ensemble of louder instruments such
as shamisen, shakuhachi, or percussion (mostly every instrument),
it is strongly recommended that it sounds in a reasonable acoustic
condition in terms of texture of the ensemble as an acoustic context.
On Kokyu playing, the body of the instrument is spun by left hand
that also holds fingerboard, when moving form one string to another,
unlike the string alternation on violoncello that depends on the
angle of right had that holds a bow.
Below are two standard tunings of Kokyu.
Derived from above, two interval types of tuning (chromatically
transposed) are available.