Would elevating a sub off the floor lessen the amount of bass going through the floor? It's a hypothetical question as I don't have a sub yet, but wish to get one for my apartment. I live on the top floor and am concerned about pis*ing off the people below me. Would it also affect sound quality? I've heard that bass is "omnidirectional" so it shouldn't matter, but don't know if I buy that or not.