Here's what I did, if yo have a base stereo in your JK and afraid of getting a new headunit stolen then here's what I did.. and it sounds a bit better than the 325 watt monsoon that was in the car traded in for my Jeep!
Do the 6.5" speaker upgrade. Be sure to stuff the speaker boxes and sound bar with polyfill. It's worth it.
Get the kicker 33 amplifier upgrade. Do it. You will notice your 6.5" speakers are louder.. more dynamic range but no bottom end yet. until the last step.
get a 10" sub.. I had an old punch Z in the basement. I bought the 10" sub woofer box from Wallmart for $29.00, and a Rockford Fosgate 150-2 amp from
Ultimate Electronics for $90.00.. buy a PAC linelevel converter with amp remote
Wire it up, make sure you connect the sub speaker level out to BOTH channels of the PAC converter. This is required for the remote power on
to work. Wire it up as bridged.. you will have 300watts out to your sub.
turn on your factory head unit, set the bass to 0
slide the rockford fosgate pass filter to low pass.. adjust notch filter to your liking... I'm around mid... adjust gain to get maximum punch and reduce the distortion to 0.
get in the jeep and adjust to your liking. ahh.. now I can listen to
Seether, Stone Sour, Alter Bridge, Shinedown... without wishing the jeep
had a better sound system! It rocks!
Total power is @ 485Watts RMS!
I can still fit three duffle bags and a cooler in the back! I'll post pics