I know for a fact that a lot of my current sub's bass travels to my neighbor's townhouse (attached to mine), and I don't want to disturb her too much. I've read where some people have put different types of materials underneath their sub, which I believe was done to help decouple the unit from the floor and thus reduce the amount of bass that escapes the room. I hope to upgrade to SVS soon, and was wondering if this is a good idea for SVS subs. If so, what should I put underneath the subs? I've seen some who have bought a slab of concrete from Home Depot for underneath. Any thoughts on the best material for underneath an SVS, and is this recommended for SVS subs? Also, what affect will this have on in-room bass response?