Need some help on a new setup for my 2000 Explorer. I just got my Sirius radio setup and it has my music interest up again. Somewhere in the $1000 range. Looking for more SQ than volume, especially in the sub area. How to get the best bang for the buck? What should I replace first? Thinking: HDU - Alpine CDA 9825, ? Fronts - components of some kind - Infinity, CDT, ? Rear - component or coaxial ? Sub - hear good things about ED, but which one, where do I put it? Amp - ?