Slate under speakers?

Fishboat. Slate doesn't make sense. You would be better off with less density, surface area etc. Blindjims idea of plywood or even MDF would be much better on carpet. Wrap it with felt to make the wiff happy. The sound will just resonate back through your cabinets if you use slate. It doesn't work.

Zargon. I'm just theorizing. It seems to me that slate or granite would resonate, where as MDF or plywood would not. If I were using slate or granite, I would put it on high density foam and not a lot of it, to cut down on how much surface area is touching the carpet. If you're going from having your speakers spiked to the floor (coupled) to putting them on slate on top of the carpet (decoupled), you will surely notice a difference for the better. Not the best though. You've still got something very heavy and dense, condensing the carpet fibers and slightly coupling itself to the floor, especially because of how much surface area there is with a slab of slate or granite. Companies such as Aurelex have done extensive research on this subject and that's why their line of products for decoupling amps (isolation risers) have very little surface area that touches the floor, yet very large surface area for the amplifier up top. The reason this phenom of slate and granite started was the WAF factor.....really. That's how this all got started. Then everytime somone posted the question, people would reply "I use slabs of granite. It made a big difference and it looks great", and everyone started doing it. I'm not saying it's a bad solution for carpeted floors, but there's better out there IMHO.