I agree with focusboy5. You can add an LOC and add an amp and sub no problem. I did this in my 2003 ZX3 and ran it like this till the factory head unit gave out a month ago. It took about three hours to do the whole install. You can check it out at my cardomain page.
I agree, the LOC is the way to go to add and amp that can't be added to your stock HU. I got one from the local radio place, wired it in to the rear left and right speakers, voila, rca connections for my amp. I use a 400w pushing a single 12, works pretty good. Getting ready to add the Triptunes for my mp3 player, cell phone and the portable DVD player for those road trips.
i purchased a powered subwoofer from crutchfield today, the Bazooka tube BTA6100. i think it will be enough to add some decent bass and it shouldn't be too hard to install for a beginner. it came with the F.A.S.T. cable so it should plug into my stock singleCD hu, right? all i have to do is get an amp wiring kit i believe.
I thought Bazooka's came with everything you need but I'm not sure. Powered sub is a good way to go, however speaker level inputs often sound like crap. Get a line output converter. You will be amazed by the difference for virtually no extra work.
If you go powered sub, I would suggest the Kenwood. It will put out a ton of clean bass, has a 200W class D amp, and cool remote.
tell us how it works out sirjohn, i was just looking at the litle powered subs last night. i want t oadd some bass eventually when i get money but am not really into the whole huge box, 2 12s thing anymore. dont get me wrong i used to be, but now i use my car for carrying supplies and whatnot and it wouldnt be practical.
this thanksgiving im going to install the sub and i'll post some pics up for ya. it'll be probably on the 28th that i get the pics and review up. i'm in knoxville and the sub and other junk is in memphis