Koto scales and tunings

Abstract

The koto, an instrument consisting of 13 strings stretched over a long sounding board, is tuned by a set of movable bridges, one for each string. The koto's musical range normally extends from A1 to A7. Within this range, two and a half octaves are most commonly utilized. Excluding modern pieces, most koto pieces are constructed from a five‐tone scale. Generally classified, there are two types of scales that can begin on any tone; a minor‐sounding scale (mi‐fa‐la‐si‐do‐mi), and a major sounding scale (re‐mi‐sol‐la‐si‐re). The most common tuning is known as Hira‐jôshi, which begins on the fifth string of the koto and follows the minor‐sounding scale noted above. Tuning on the koto is accomplished by first setting string No. 1 to the desired pitch. Then the fifths, fourths, octaves, firsts, and minor seconds are tuned, creating a scale close to the Pythagorean scale. Like piano tuning, inharmonicity is observed. Several of the traditional tunings for koto music have the same scale as the minor‐sounding Hira‐jôshi except that they begin on a different string; No. 6, 7, 8, or 9, rather than string No. 5. Likewise, the major‐sounding scales can begin on any of the same five strings.