Air-wood coupling and the Swiss-cheese violin.
Some problems with the conventional formalism for describing the coupling of fluid vibrations to those of an enclosing shell are examined. An alternative ("dynamic") basis for expanding the normal modes, in which the "pure shell modes" include incompressible motion of the fluid, is proposed. This new approach is applied to Hutchins's "Swiss-cheese violin," the behavior of whose air modes for the case of a rigid shell have been calculated by Shaw. Measurements are presented of various response functions of this instrument as a function of both frequency and the number of open rib holes. These results show the predicted "mode veering" behavior, and can be easily matched to theory with the assumption of plausible parameters.
Weinreich
G
G
Randall Laboratory of Physics, The University of Michigan, Ann Arbor 48109-1120, USA.
Holmes
C
C
Mellody
M
M
D000161:Acoustic Stimulation / Q000295:instrumentation; D000388:Air; D004867:Equipment Design; D015233:Models, Statistical; D013016:Sound; D014732:Vibration; D014934:Wood