Vibration Isolation & Damping Defined & Differentiated

Read This Before You Buy Anything!

Prospective buyers of vibration control products should know the basic definitions of, and the distinctions between ISOLATION and DAMPING to enable them to make informed purchases. BOTH vibration Isolation and vibration damping are essential for ultimate high-end audio performance.

A Vibration ISOLATOR is a viscoelastic part or a device that provides relative movement between the supported component or loudspeaker and the supporting structure, ie: the rack, a platform or the floor.

A Vibration DAMPER is a viscoelastic material or a device that converts vibratory energy into heat - thereby dissipating the vibratory energy.

In an automobile, the springs provide isolation and the shocks provide damping but they are not interchangeable! They are interdependant!

FOR AUDIO / VIDEO, THE BEST PRODUCTS ARE THOSE THAT PROVIDE ISOLATION AND DAMPING!

ISOLATION refers to the process of preventing (minimizing) externally generated vibratory energy from reaching a structure or component. Although this includes acoustic or air-borne vibration that is difficult to manage in exposed audio/video equipment, we are primarily concerned with the transfer of mechanical vibration. And, it is essential to understand that there is no significant mechanical isolation provided unless there is relative movement between the component or  loudspeaker and its supporting structure to prevent sympathetic movement with the supporting structure. Therefore, only a device or material that can compress like a spring or deform like an air-bag or a viscoelastic part, or “roll” like a bearing, can be an isolator. Exceptions to these “passive” examples include “active” systems that have electromechanical capabilities. Obviously, hard “spikes”, "cones", and (bare) "platforms" or "shelves" are not vibration isolators regardless of their material composition! However, a platform supported by isolators as part of its design can be an isolation platform.

DAMPING is the dissipation of energy in an vibrating structure or component. It refers to the process of removing (minimizing) internally generated vibration that is inherent in a component AND any external vibration that, for lack of adequate isolation may enter the component, by converting the mechanical vibratory energy of solids into heat energy - a process called hysteresis. Vibration damping is generally accomplished by the bonding of viscoelastic materials to the (vibrating) internal surfaces, mechanisms and parts of a component and by external coupling to viscoelastic materials or damping devices.