I have a floating wood floor that was not working well with my subs. The subs were boomy and shaking the room. I installed Iso Acoustic feet on the subs and the problem was solved. I'm now very satisfied and you can't "hear" the subs in the system.
Vibration dampening
After reading the article on Herbies isolation products, I got to thinking: My sub has more vibration going on than anything else, at higher volume you could put your hand on top and it feels like a massager..I am using spikes on thin carpet with concrete underneath. Has anyone had positive results with these or other isolators? It is a Velodyne DD12.