I will be the first to admit i don't know much about car audio, but I want to build a nice system with a nice blend of spl and sq....As far as a HU, I have a Alpine CDA-9815...not the newest style, but I got it for a 100 bucks. I will have to do it in steps so any suggestions? I don't mind paying for quality pieces, but as I said I can't aford to have it all done at once. I have a 92 Mercury Grand Marquis. Thank you for taking the time to read.