On the factors for detecting mistuned conditions and guiding their corrections for the Koto tuning

Abstract

By observations at the Koto tuning practice, it is realized that the bridge is moved in the period of about 400 ms, which is too short to feel the sensation of beat. Then, two kinds of listening tests were planned. The test sounds composed of two Koto sounds which should be tuned in one octave interval were presented at the same time like a part of actual Koto tuning process. The lower tone was at 196.9 Hz, the pitch of the higher one was varied in the range of 20 cents. Their length from the beginning was varied from 50 to 500 ms. The first experiment is for the judgment of the right or wrong tuning (higher or lower). The second one is for the tone color impression using 13 pairs of adjectives. The results of these experiments show that reasonable pitch judgments can be done for the test sounds longer than 200 ms by well‐experienced Koto players, and the test sounds are clearly distinguished from each other by their tone color difference, whereupon in the Koto tuning by expert players, the direction and degree of mistuning are found to be judged at the initial stage of Koto sounds by the tone color impression.