Unlike most amps, the Sunfire's disperse the majority of heat from the bottom plate of their chassis. As such, the chassis should be elevated with plenty of air-flow allowed to pass underneath and around it. This is one of the reasons that the amp itself seems to run so cool to the touch i.e. you're touching the top and the heat comes out of the bottom. Rigidly coupling the bottom plate to taller metal cones not only helps to elevate the chassis for improved air-flow, it also adds more surface area to the heatsinking area and can aid in draining mechanical vibration from the chassis mounted transformer to the support shelf below it. Adding a small but evenly distrubuted amount of weight across the top of the Sunfire amps also seems to help damp cabinet resonance.
Sorry i'm no help pertaining to the Siesmic Sink : ) Sean
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