Abstract: An exemplary inventive device is placed between inner and outer concentric cylindrical structures. The inventive device includes at least three coaxial rectangular-toroidal elements adhered together, viz., at least one smaller stiff element, at least one larger stiff element, and at least one resilient element. The elements are arranged so that each resilient element is adjacently positioned between a smaller stiff element and a larger stiff element. The inner circumferential surface of the smaller stiff element contacts the outer circumferential surface of the inner cylindrical structure. The outer circumferential surface of the larger stiff element contacts the inner circumferential surface of the outer cylindrical structure. The inner and outer circumferential surfaces of the resilient element are distanced, respectively, from the inner cylindrical structure's outer circumferential surface and the outer cylindrical structure's inner circumferential surface.

Abstract: Apparatus and method, having both structural and acoustical applicability, for measuring damping of a solid or fluid resonant physical system in terms of reverberation or decay time, featuring a digital computer-based measurement system in which plural numbers of resonances are grouped into single analysis bands. The resonant response is converted into an electronic signal, which is then pre-amplified, filtered, post-amplified, digitized and finally processed so as to determine the reverberation time in the resonant physical system.