The role of modal analysis in stringed instrument design
Mark N. French · The Journal of the Acoustical Society of America · 2005
The modal response of stringed instruments clearly contributes to sound quality. Modal analysis was applied to stringed instruments shortly after commercial data acquisition system became available. Even now, the most sophisticated equipment has been used on instruments. In spite of this effort, there is no consensus on the relationship between modal behavior of an instrument and sound quality. Useful guidelines have been developed for the lower modes of guitars and violins, but these are necessary, not sufficient conditions for superior sound quality. It now appears that superior sound quality is based on more subtle interactions of the dynamic response of the acoustically coupled structure and its material properties. Understanding the modal response of the instrument is still extremely useful. The acoustic-structure interaction of the first two or three modes of the instrument clearly demonstrates the basic physics and forms the basis of discrete models that are very helpful in considering the first-order effects of instrument modifications. The modal response of an instrument can also be critical in placing sensors to be used as pickups. Accelerometers are being used to augment piezoelectric bridge pickups and more traditional inductance pickups and their placement greatly affects the resulting sound quality.