The modal active control proves to be a suitable way to modify the radiated sound of musical instruments. Beyond this attribute, the control can be used as a tool to study the physical phenomena governing musical instruments' performances. Thanks to this technique, many points usually analysed using synthesis can be studied directly on the instrument. For example, the active control enables the in situ investigation of the mechanical properties' effects on the sound of the instruments.

This paper proposes to compare the abilities of active control with these of a physical modeling synthesis method. An classical guitar is used as subject. The advantages, the drawbacks and the limits of these two tools are investigated and discussed.