Abstract
In this study, we propose a method for automatically detecting musical scales from Japanese musical pieces. A scale is a series of musical notes in ascending or descending order, which is an important element for describing the tonal system (Tonesystem) and capturing the characteristics of the music. The study of scale theory has a long history. Many scale theories for Japanese music have been designed up until this point. Out of these, we chose to formulate a scale detection method based on Seiichi Tokawa's scale theories for traditional Japanese music, because Tokawa's scale theories provide a versatile system that covers various conventional scale theories. Since Tokawa did not describe any of his scale detection procedures in detail, we started by analyzing his theories and understanding their characteristics. Based on the findings, we constructed the scale detection method and implemented it in the Java Runtime Environment. Specifically, we sampled 1,794 works from the Nihon Min-yo Taikan (Anthology of Japanese Folk Songs, 1944-1993), and performed the method. We compared the detection results with traditional research results in order to verify the detection method. If the various scales of Japanese music can be automatically detected, it will facilitate the work of specifying scales, which promotes the humanities analysis of Japanese music.
