For those of you that want extra bass, without the lost of your trunk, this is your solution!
See this thread for details.
http://legacygt.com/forums/showthrea...38#post1870838
The 4th gen guys have had these for a while, but I was the first box he made for the 5th gens, and let me say, it sounds incredible!
Line out converter
Amp underneath passenger seat (seat pushed forward to show, normally you can't see it).
This is by far the best option for a sub IMO. It provides REAL bass, unlike the underseat subwoofer and the HK sub.