I just bought an 07 Eddie Bauer 4x4 to replace my 03 Expedition XLT. I heard somewhere that the entire factory Audiophile stereo, plus factory subwoofer & speakers, work as one unit. Is this true? In other words, swapping out factory speakers for aftermarket or swapping out the factory sub or adding a more powerful amp will ruin the sound quality of the entire system. Although the factory unit sounds impressive, I figured that changing out the factory speakers for Infinity reference series and possibly adding an amp would not hurt, but I don't want to make it sound worse either. I intend to swap out the factory stereo as well with a double din unit. Any suggestions?
