Patent ID: 7562617

Claim:
A mounting apparatus that comprises: a first ring having a first surface and a second surface; a second ring having a first surface and a second surface, which second ring is movable with respect to the first ring; a first flexible diaphragm attached to: (i) the first surface of the first ring along a first-surface-first-ring attachment perimeter that encloses a first effective surface area, and (ii) the first surface of the second ring along a first-surface-second-ring attachment perimeter; and a second flexible diaphragm attached to: (i) the second surface of the first ring along a second-surface-first-ring attachment perimeter that encloses a second effective surface area, and (ii) the second surface of the second ring along a second-surface-second-ring attachment perimeter; wherein: the first and second flexible diaphragms and the first and second rings form a chamber with one or more intake apertures; and the first effective surface area is different from the second effective surface area.