you can tap into your head units front and rear power if you get a wiring diagram and bridge it down front and rear but I highly dont recomend it you will be giving your stock units amp a 2ohm load also like 3 watts to your subs without a x-over. not a good idea at all!
i do do that, i use the regular speakers wire but they sound like regular speakers, i want it to sound like subs with out putting a new headset in and use amps with it
alright I am lost here. do you have an amp or no? are you trying to run the subs off of your deck and have it sound clean? that wont work! The only way you can run that is to run a bass blocker that will run a cut off at 80 htz to your subs. With only litterally at best 5-10watts of power you are not going to get decent sound out of your subs unless you have a pair of subs from the early 80's with a 25watt rms power rating. what kind of subs are they? I need more info as to exactly what you are trying to do.