I have a sealed box that I bought for my Trans Am (well, Firebird back then, before I upgraded) about 7 years ago. I love the way it looks, and it allows me to store my T-tops in the rear. It was made for 2x 12" Kicker L5s, which I just got rid of because they sounded sloppy. They were loud, but not in a great way. I am in the process of modifying the box to allow 12" circle subs, and each chamber will have around 1.1cu ft each. I want my setup this time around to be a little cleaner and sound better. Last year I installed some CDT components up front, with 6.5" CDT woofers in the rear. I plan on powering them with a PPI P900.4, just waiting to make sure it will fit in the spot where the stock Monsoon amp was. Car is in storage, damn weather up here isn't cooperating for me to get it out just yet. I plan on powering the subs with around 1000-1200W @ 1ohm (amp still unknown), so looking for two DVC 4ohm subs. I listen to all types of music, mostly mainstream, from rock to rap, pop to country. I basically want a clean sounding system that can still hit hard. My old L5s hit plenty hard, but that was about it. My main choice right now is a pair of SA-12s, because of all the good press they've gotten. But other subs on my radar include the Fi X12, C2 Audio Threatcon 2, I was even thinking of the GCONs but they are a little out of my price range. I want to spend around $400 shipped, less is better. I am a bit flexible on this, say a pair of subs that are $30 more will sound much better, it would be a no-brainer not to go with them. I can get b-stock SA-12 D4 for $160 each, for what its worth. With all that said, what makes a sub geared more towards a sealed enclosure? I've read that a higher Qts will sound better in a sealed enclosure, while a lower Qts is more for ported enclosures. Is there truth to this? Somewhere I read that SA-12s are more for ported enclosures, but it wasn't a credible source. Just wondering if I should be looking at other subs than what is on my list at the moment, or if I am headed in the right direction. I've been reading a few posts on this forum and you guys seem very knowledgeable on the subject of car audio, so I look forward to your advice. Thanks.