Just was thinking about all the confusion on whether to set your speakers full range (large) or set them to small even if the specs say they can go to 18hz (my Def Tech BP30's). To achieve 20hz @ high spl at the seats is it dependent on the drivers/cabinet or the amp/current use to drive them? Of course if there is any speaker that can actually (honestly) obtain these levels. Is there? Wilson, Dunlavy, B&W, Krell, BP 3000's ect..