The necessity of a plinth

As much as we wish they were, cones do not act as diodes.

Cones have the shape of the electrical symbol for a diode but this doesn't mean they act as (mechanical) diodes. Btw, why should mechanical devices act like electric devices and vice versa? Personally I think the mechanical diode theory is not a scientific one.

Chris

This has absolutely nothing to do with the differences between DD tables and idler tables, but IMO a cone-shaped footer can be an asset IF one first determines the loci of standing waves on the shelf (which would be based on the resonant frequency and is best located with a stethoscope) and then places the tip of the cone on a vibrational node (i.e., a point where the shelf is not vibrating). This would then prevent the shelf from transmitting vibrations up into the equipment, because the equipment would only "see" the null points in the shelf. Like you guys, I don't quite see how a cone will prevent transmission of energy in the other direction. However, is not a diode a one-way device? Ergo, we have a mechanical diode. Maybe the term "diode" is not semantically appealing in this case.