Ok I currently have a tc t1000 12" for the sub section of my system, and enjoy it. I like the sound of it and loudness, i built a 2.2cf sealed box for it and it plays low. Now the problem is I need my trunk space back, all of it if I can, since we have a little one on the way. The options I have looked into are 6.5inch subs in the rear deck (6x9 holes there now), tang band 6x9 subs, thought about trying to fit 8s in the rear deck, or a small dual 8 box in the trunk. Something in the less than 1cf range. Now I know I'm going to lose volume, and but I still would like some bass. I have an a/d/s 345 comp set up front. Oh and I have 2 or 4 ohm for the potential sub 400w at 2ohm. Let me know what you all think, is using the rear deck IB even a real option for anything below 40hz? I would like to do this for about 100 bucks in speakers, used is fine.