Control and coordination in complex bowing patterns
Erwin Schoonderwaldt

Detailed measurements of bow motion in the performance of musical pieces can give new insights in subtle aspects of control in tone production by string players. I will present detailed analyses of arpeggio passages across two and three strings in several performances of the Preludium of the third Partita for solo violin by J.S. Bach. The bowing patterns are characterized by a quasi-periodic motion of the bow, which can be visualized as Lissajous curves. The two movement components corresponding to bowing the string and string transitions show an interesting phase relation, where the string crossings slightly lead changes in bowing direction. An acoustical explanation for this behavior is that it results in clear attacks, and this can therefore be considered as a good example of optimization in human sensorimotor learning. A comparison will be made between performances by two advanced players, one of them familiar with the piece, and the other one sight reading it, as well as a performance by an amateur player.