I am considering getting a Refurbed 4.1 set, and don't really have the desk space for the sub. If I put it on the floor, well, my manager lives directly below me . Both good and bad. I've heard about spikes put on subwoofers to isolate them from the floor and supposedly improve frequency response. Would this help to isolate a subwoofer from transmitting sound to the floor better? I have no doubt that the Promedias can shake the floor as well as the walls.