I'm going to buy a cd player/receiver very soon, and was curious what the RCA Preouts are? Im guessing that's where you plug in the speakers etc, but why do the ads say "RCA Preouts" for some (the s lets me think their is more than one preout) And the more expensive decks have "Dual RCA Preouts". All I want to plug into the receiver is the 2 speakers that come with it, 2 old speakers that are in the front of the car, and a box with a 10" Rockford Fosgate (sp?) sub. I found a deal that I get a 10" Rockford sub and a box for 99.95.