dont want to fm modulate

a friend of mine is selling his car and giving me his jvc 12 disc mp3 cd changer. This cd changer only has one imput at the changer itself which is like a s video style plug round with a bunch of pins. this goes to a fm modulator that wires in to the antenna of the car. i asume this style is better than the kind that is wireless and transmits the signal via air. I was wondering if i could hook this unit up via rca inputs on the back of the HU.             Thanks in advance