Fraunhofer Institute for Building Phys
Abstract :
Cross-fingering is a technique of playing woodwind
instruments in which one or more tone holes are closed below
the first open hole. It usually yields a pitch lower than that
played with normal fingering. However, pitch is raised in
exceptional cases. Pitch flattening has been traditionally
understood using the lattice tone hole theory. On the other
hand, pitch sharpening has been scarcely explained except for
pointing out the possibility for the open hole to act as a
register hole. This talk proposes understanding these pitch
bending phenomena in a unified manner with a model of two
coupled mechanical oscillators. Bores above and below the
open hole interact with each other by sharing the air in the
open hole oscillating as a lumped mass. This mechanism is
known in physics as avoided crossing or frequency repulsion.
With an extended model having three degrees of freedom,
pitch bending of the recorder played with cross-fingering in
the second register can also be explained.