I currently have 2 x 12" Memphis PRs running in a 4 cube box tuned to 40hz and it is alot louder than most would believe, (ask ghostface if you dont beleive me) they are running about 600 watts @ 4ohm wiring. would a single atlas 15" be as loud on the same 600 watts? Would the SQ be better? SQ on the PRs is not so hot (probably because of the 40hz which is also probably why it is so loud).