Abstract
Free vibration analysis for guitar considering coupling of strings and body is carried out. To estimate sound quality of a guitar by using CAE, we develop FEM model considering coupling of strings and body In the FEM model, tension of strings is treated as internal force. Eigenvalue analysis is carried out and the modal strain energy method is applied to calculate modal damping. Mathematical model for playing guitar is proposed and calculation method of initial displacement of each mode is demonstrated. By using the proposed method, we examined the effect of stiffener on the modal damping ratio and initial modal displacement. through the discussion, it can be seen coupling revel of strings and body has very strong effect on the modal damping ratio and initial modal displacement which has strong relationship to the sound quality.