I spent a little under 1K on my car audio stuff:
HU: Pioneer Premier 730 ($260 shipped)
Doors: 2 pairs Audiobahn ACX680P 5x7s/6x8s ($97 shipped)
Subs: 2 12" audiobahn 1200eu's ($187 shipped)
Amp: Audiobahn 2200HC - rated 1600watts @ 12.5 volts ($350 shipped)
Thats $900 for the above, plus an amp wiring kit from KnuKonceptz, a 140 amp circuit breaker that was $50, and I'm going to have to get a capicator or a second battery with an isolator because my lights are dimming when my amp hits. I'll probably end up spending around 1200 total, but my amp retail is a grand by itself, so for the quality of sound in my car right now, I feel very good about all my purchases. I've noticed a lot of people that knock on audiobahn, in my personal experiance all of their products are top of the line in build quality and sound quality, I guess people just can't accept the fact that you can get that quality at a good price if you shop around. I got lucky on the amp and subs, they are normally 1K for the amp and $199 per sub, I got em when they were blowing out last year models for super cheap.
Biggest factor in reducing price, I installed the HU myself, had a CEGer with car audio experiance (2gsport) help/teach my how to do the door speaker, and had a custom box built for the subs and he once again helped me install everything. I have no doubt in my mind that if I had the same exact hardware installed and purchased thru my local audiobahn dealer, I would have been well over 3k by now.
just my $.02.
