Experiments of acoustic resonance and vibration mode of kotsuzumi using paper pipe, V-shape pendulum, and carbon paper

Kotsuzumi is a membranophone used in the traditional Japanese performing art of Noh. So far, there are few studies about kotsuzumi. In this study, to reveal the component of kotsuzumi’s sound, we experimentally verified the acoustic characteristics of kotsuzumi. Acoustic physics experiments were conducted using paper pipes, clay, pendulum, and carbon paper. Loudspeaker and microphone were used to produce and record sound, respectively. First, the characteristics of the acoustic resonance inside the difference cavity shapes of the bodies were measured. Second, vibration modes of the membrane and the body were measured. Finally, a professional performer played kotsuzumi to verify the measured acoustic characteristics. We found that a sound around 200 Hz was due to (0,1) mode of the front membrane of kotsuzumi, a sound around 800 Hz was due to the characteristics of the body as a resonator, and a sound around 1580 Hz was due to the vibration of the kotsuzumi’s body itself.