I read through several old threads and I still don't feel like I have a good answer to this, so forgive me for asking what I'm sure must be a phenomenally simple question. What's the best thing to do with my subwoofer, regardign it's contact with the floor? It sits now on carpet (approx. half-inch cut pile) with padding underneath and plywood flooring below that. Would I see any benefits from spikes, a heavy stone slab below, a heavy stone slab above, or some combination thereof? Because it is on carpet, I did not install the little rubber discs underneath it that came with it, though I do still have them. If I go with the stone slab beneath, should I add those? Thanks in advance.