My Linn was absolutely unusable due to my springy floors, but the problem was totally cured by the Target shelf. I expected some improvement, but not the virtually total isolation I achieved. The dog can jump down off the couch and not a flutter. Another good thing about the target is that you can easily change shelf materials - At least in the case of the Linn, the sound changes substantially with what it sits on. I've found Corian works the best for me, but it's easy and cheap enough to try a piece of glass, wood, or whatever.