ASA 129th Meeting - Washington, DC - 1995 May 30 .. Jun 06

2aMU4. Effects of bow-hair compliance on bowed-string motion.

Roland Pitteroff

James Woodhouse

Cambridge Univ., Eng. Dept., Trumpington St., Cambridge, U.K.

Bow--hair compliance is likely to have a strong effect on bow--string interaction. The first line of evidence comes from analyzing experimental results presented by Cremer [L. Cremer, The Physics of the Violin (MIT, Cambridge, MA, 1985)] of the reflection and transmission behavior of transverse waves on a string incident on a bow at rest. The second line of evidence comes from simulations of the bowed string taking into account the finite width of the bow. The nature of the ``differential slipping'' which may arise due to the kinematical incompatibility of uniform bow velocity across the width of the bow and the string velocity in standard bowed-string motion (Helmholtz motion) is strongly dependent on bow--hair compliance. Simulations also demonstrate that suitable tilting of the bow can reduce the extent to which ``differential slipping'' is detrimental to the establishment of the desired string motion. Preliminary results of an experimental investigation of finite bow-width effects will be discussed.