Analytical Study of Acoustic Mechanism of “Suikinkutsu”
Yoshio Watanabe · Japanese Journal of Applied Physics · 2004
In this report, I describe an experimental analysis of the acoustic mechanism of the suikinkutsu. The sound of the suikinkutsu consists of an original sound generated by water drops striking the surface of the water in the suikinkutsu and a reverberant sound generated by the original sound. The reverberant sound is the sound we hear through the observation holes of the suikinkutsu. The body of the suikinkutsu also has its own natural frequencies and vibrates in synchronism with the natural frequencies of the oscillation modes of air inside it, affecting the tonal quality of the sound emitted from the suikinkutsu. If all of the natural frequencies and time constants of the reverberant sound are optimized, the suikinkutsu can produce a sound of good tonal quality. In this study, we investigate the relationships between the original sound and the reverberant sound emitted from the suikinkutsu. We propose an experimental formula representing the natural frequencies of the suikinkutsu and examine the validity of this formula.