Development of practice support system for violin bowing

Recently, there has been an increase in the demand for playing musical instruments at home, primarily because of the restrictions enforced due to the COVID-19 pandemic. We propose a system that can automatically estimate the angle between the bow and the string of a violin during playing from the playing sound and provide feedback to the player to realize a violin bowing practice support system. In this study, the automatic estimation of the angle performed using harmonics structure of the violin tone. The angle between the bow and the string were estimated using the ratio values between the harmonics level in the low frequency band and the level in the total frequency band. It was confirmed that there was a significant difference in the ratio between the sound played at a right angle and the sound played at an acute angle of approximately 20-30 degrees from the right angle. We are developing a practice support system using this method. The system judges the bowing angle to be good or bad and provides feedback to the player using LEDs. In full paper, we will describe the bowing skill identification method on the system in detail and report the evaluation results of the system.