Can i install a subwoofer in my car with the factory head unit? or do i need an aftermarket head unit?

Question

its a 1997 ford escort

Answer 1

no, you can get an in-line converter. a small converter that has 4 speaker wires on one side (L and R + and -) and a set of RCA's on the other. wire it in to a set of speakers (usually the rears) and run the  RCA side to the amp and the amp to the sub. the converter will not effect your rear speakers, it just transfers the signal to the amp.

Answer 2

No, you dont need an aftermarket head..What you will need is one of two things.

1.An amplifier that has line level inputs. Basicly an amp to power the sub that has inputs that allow you to "Branch" off your rear speakers and feed the signal to your subwoofer.

2. A line level converter if the selected amp only has RCA inputs. The converter is a little box that takes that high level output (again from your rear speakers) and lowers the power down to a level that will work with the RCA inputs.

A quick note tho. If you choose to use your rear speakers as the source for your sub input you will not be able to tune your system correctly. (Basicly if want more sound from the rear speakers, you cant adjust them without adjusting your sub.)

Answer 3

Yes you can use your factory head unit but you need a line converter that converts the factory speaker output lines into rca inputs to the amp.  I assume you want to use an amp to run the sub.