I have two 15"s right now and I have grown out of my basshead phase. I want something that will have better low end extension than my PG's, and I want to go with a single woofer. Whatever I get it will be in a sealed box. I want to go all out SQ. Not worried about SPL. I'd like to keep it to 200 or less, but if spending an extra $50-$100 will get me better SQ, I can save up. I have 1500 watts (probably overrated) at 1 ohm, 1000 watts at 2 ohms. I like to keep the gains set conservatively, and I think headroom is good. What woofers would fit this application?