adding a subwoofer

[sggity]

I want to add a subwoofer to my car. I have the original radio unit (no navi). do I have to change this unit to add a sub with an amp? what about a sub with a built in amp? can I keep my original radio unit??

[vernitez]

u can continue to use the headunit. had no prob wiring to 3 amps.

[sggity]

Thank you so much. I finally bought a sub and an amp, can you explain how I might go about doing this? I believe the wires are fiber optics, I'm sort of lost. Maybe I should take it to someone professional?