Abstract
Koto strings had been made of silk fibres until a few decades ago, but silk strings are susceptible breakage during performance. In recent years, ordinary polyester strings are almost always used. However, many players love the tone quality of the silk strings. Therefore it is important that a Koto string is developed which has the tonal quality of silk but of greater strength. We thougth the tonal quality is affected by the fibre shape, and developed strings using silk-like polyester fibres. The physical tone properties of the Silk-like polyester strings and the ordinary strings were investigated with a FFT analyzer. The tone of silk-like polyester strings included a lot of high-fre-quency components as compared to silk strings, and the tone of silk strings mostly consist of basic mode and over tones of basic mode The tone of silk-like polyester strings include various frequency components. The frequency properties of silk-like polyester strings resemble the ordinary polyester strings.
