Koto

Kazue Sawai performs a piece on the koto.
This instrument is a stringed instrument belonging to the zither family, introduced to Japan from China during the Nara period (710–794 AD).
At first, the koto was used for a long time only at the imperial court. This changed in the 17th century, primarily thanks to the work of Yatsuhashi Kengyo (1614–1684), who worked to make the koto more accessible to the general public. He developed a new tuning, called hirajoshi, which became one of the most widely used, and created compositions for this instrument that have become literary classics, such as Rokudan and Midare, the piece we hear here.
This is therefore an example of 17th-century Japanese classical music.
It is interesting to note how highly formalized Japanese classical music was. This piece, for example, belongs to the category of danmono, a classical form of instrumental-only koto pieces, composed of different sections called dan [lit. "step, shelf, level"). In the most traditional form of danmono, each dan is made up of 104 haku [pulse, beat, fundamental unit of time measurement] and constitutes a variation on a single theme.
This piece, however, is an exception because the various dan are not made up of the same number of beats, which is why it is titled Midare [乱 lit. "confusion, chaos"].

Regarding the koto, the body of the instrument consists of a sound box, about two meters long and between 24 and 25 cm wide, generally constructed of Paulownia wood (Paulownia Tomentosa, or kiri in Japanese). Thirteen strings of equal diameter and equal tension run across it, each resting on a movable bridge (ji, 柱).
This fact should be emphasized because it is a completely different system from the Western one, in which strings of varying diameters and tensions are used.
Here, the strings are all the same size and pulled to the same tension. Therefore, to obtain different notes, the only way is to vary the length of the string. In fact, each of them has its own bridge, which is placed in different places.
The strings are then plucked with the right hand, while the left hand does not play, but creates embellishments in the form of vibratos and quick glissandos, both in the attack and at the end of the sound, obtained by pressing the part of the string that is beyond the bridge. Naturally, the fact that all the strings have the same tension facilitates this task because a given pressure generates a glissando of the same length on each string, which would not occur if the tension were different.
The player kneels or sits in front of the instrument and plucks the strings using three plectrums (tsume) attached to the thumb, index finger, and middle finger of the right hand.
Koto sheet music is generally presented in tablature form, read from top to bottom and from right to left (the normal reading direction even in modern Japan: books are laid out this way, although horizontal writing is now also common).
The koto is compared to the body of a reclining Chinese dragon. For this reason, its various parts are given names reminiscent of those of the mythical animal, such as:

Ryuko (dragon's back): This is the upper part of the soundboard.
Ryuto and ryubi (dragon's head and tail): These are the extremities of the instrument.

Kazue Sawai is considered one of the greatest living virtuosos of this instrument.

Now, however, we see the same performer engaged in a contemporary composition for koto.

Composer: Tadao Sawai (Compiled in December 1988. To commemorate the tenth anniversary of the founding of the Sawai Koto Institute. First performed by Kazue Sawai)

The 17-string instrument, invented by Michio Miyagi, has a history of approximately 70 years (note: at the time of this composition), and has far outgrown its original purpose as a bass supplement, and has recently been used as a solo instrument. Of course, the process of reaching this point is due to the great efforts of performers, composers, and the people who create the instruments, but the depth and strength of the 17-string's sound, as well as the length of its lingering sound, are important factors. Its charm will continue to capture people's hearts. And now it seems Jushichigen is becoming the flagship of the Japanese music world. [Text: Tadao Sawai, Google Trad.]

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