fluid current induced vibrations , as well as vortex shedding vibrations induced in a cable stay or a similar elongated , cylindrical element are dampened and substantially eliminated by applying a plurality of flexible active or passive damper bands to the cable at spaced intervals . in underwater currents , the damper bands force or channel the fluid flow over a circular cross - sectional shape , which inhibits lift , and therefore damps the cable stay oscillations . these damper bands can be retrofit to existing cables or can be installed on new cables . each damper band may include a shiftable mass and an energizing device for facilitating assisted shifting of the mass . a control assembly can actuate all or selected ones of the energizing devices in response to sensed magnitudes of cable stay vibration .