Audio Systems: my sub, rca phono, phono plugs

Question
hi i got a 12" sub 4 ohm and 400 wats and im just wondering how i can just hook it up to my moms 1993 jeep with out a amp ....Thank John Allen

Answer
You must know what head unit is being used.

Then, download the spec sheet to determine if it has audio or sub outputs on the back and if they are rca phono plugs.  OR you can pull the head unit out and look for the outputs.

If no outputs you must either purchase an interface box (from places like crutchfield.com) or cut into the main channel wires and make a bridge connection to feed to the subs (this is the least desirable method).

Then, the sub must have two 12v lines connected to it.  One is "always ON" which comes directly from the battery through a fuse.  It should be large wire gage, such as 12ga or bigger.

The other is the turn on wire that comes from the head unit or from the ignition which gives the turn on signal to your sub amp.

The, of course, the output of the sub amp is connected to the sub speaker.

Any questions?  Let me know.

Cleggsan

PS: I don't recommend you connect a sub to a head unit without a separate sub amp to drive the sub speaker unit.  They are not expensive nowdays.