Best SQL system I have ever heard was 2 15" JBL 1000's and 4 12" Cerwin Vega XL's in the back or a late 70's Chevy van. 15's tuned to like 28hz and the 12's to like 35hz. Front stage was 3 6.5's in each door and some huge dome style bullet tweeters. Everything was run of Hifonics VIII amps. A Zues on the 12's and an Olypus bridged on the 15's and a couple of smaller amps on the front stage. This was back in 94 or 95 and it is still the loudest and cleanest sounding system I have ever heard. Point being its the enclosure not so much the driver that determines the level of sound quality. Alot of people have lost sight of this since fart boxes and SPL specific drivers became all the rage. I love competition, but I still build all my systems to play music. So just buy a sub that has good healthy excursion and good power handling, build a enclosure for it and tune it low. You will get plenty loud and and be able to listen to all kinds of music. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif