Abstract
This study aims on to clarify characteristics of Shamisen (Japanese traditional guitar) in terms of energy propagation by using statistical energy analysis (SEA). Firstly, Experimental SEA model of a shamisen is constructed with impulsive excitation test; influence of internal cavity between surface skins is also investigated. Secondly, vibration energy propagation is evaluated with coupling loss factor (CLF) and internal loss factor (ILF), and it is shown that energy propagation from body to skin is remarkable than opposite direction especially in the frequency of shamisen sound range. Also, it is clarified that ILF of body is higher than that of skin, and they are almost consistent regardless of location. ILF of skin above 500 Hz is at the same level. Then, power flow is investigated and it is clarified that vibration of string is transmitted to the front skin through the bridge, and the vibration is transmitted to the back skin through internal cavity; the mechanism is the same as drum. Based on the result, Using the perturbation method, examined how to transfer energy to the surface leather and back leather where there is main energy exchange. Other than energy transmission between the surface leather and the back leather. Transmission from the front side to the back side via a neck to increase the vibration energy propagation to the back leather. Then, the exchange of energy between the surface leather and the back leather increases. This is thought to be a suitable energy propagation path to excitation the surface leather and the back leather more in the shamisen.
