bossobass,

Your granite "sink hole" solution is exactly what I have advocated in other threads for use under turntables.

However one thing to note about this approach: you need BOTH mass (granite) and an acoustic insulator for it to work properly. I suggest two slabs of granite sandwiching a layer of rubber. Those non slip workshop mats (that come in rolls) work well. Just fold it to get four layers. You can even sit the speaker on another layer of mats (both for additional isolation and to keep the speaker from "dancing" on the polished granite.

Regards.

Jeff Mackwood

I have my SVS sub on a carpeted floor and it sounds fine to me. Perhaps I am missing something since I never had it on any other surface. (may try moving it a few feet over to the marble floor in front of my fireplace later to see if I can tell the difference.) Wouldn't a throw rug do the trick ?

I think most have missed the point, his sub doesn't move, it rattles. The sub only moves if he pushes down on it. I own an SVS sub and have never experienced this, the cylinder shape is so rigid over braced cubes, that it can't rattle. Since this sub fires down at its own wood platform, (its feet are attatched to this platform so the driver does not fire directly at the floor), see if the platform is securely attatched to the sub. If the platform is loose, this might cause the rattle. Are the feet tightly attatched to the platform? Is your floor braced in this area? Put a throw rug under the sub and see if the rattle stops. Are your floor boards level under the sub? Let us know how you make out.