A continuously variable Helmholtz resonator for a vehicle air intake system
having a vibratory input to the resonator wall to dynamically adjust the
cancellation frequency for time-varying acoustical signals, and at least
one of mean resonator volume control, mean resonator neck length control,
and mean resonator neck diameter control whereby control of both the
dynamic and the mean properties of the resonator provides a wide-tuning
spectrum and facilitates canceling of time-varying acoustical signals.
