vibration and resonance

Thanks for the advice. My rack is 24"x24" shelves 4 high with 5/8's threaded rod holding it together. The shelves are 3/4 plywood. It is spiked to the floor and I am seriously considering putting a granite slab on top. I did get a maple shade 2" thick platform for Christmas to place my player on which brings up another question about footers(soft or spikes).

Do you have the rubber washers between the nuts & the shelves like the salamander racks do?

I built a rack from slate and threaded rods. My rack is very heavy but will wobble if the nuts aren't tight. I really crank them to make it rigid.

What floor kind you have in your room?