From Wikipedia
Constrained-layer damping is a mechanical engineering technique for suppression of vibration. Typically a viscoelastic or other damping material, is sandwiched between two sheets of stiff materials that lack sufficient damping by themselves. The ending result is, any vibration made on either side of the constraining materials (the two stiffer materials on the sides) are trapped and evidently dissipated in the viscoelastic or middle layer.Enter your text ....
The mat stack is clamped with a Michell record clamp . The Boston Mat 2 is stiff . As for VTA I made a on the fly VTA adjuster for my Ortofon arm from a helicoid lens focus ring . Thank you for you feedback