I have an pro xp 4. It comes with the Rockford stereo. Headunit, front and tear speakers with 400 watt amp. It I add the sub does that technically make it a stage 4?
No not that I can tell. I read that little hack on a forum then immediately went to the garage and boom way way louder!! Which was good because we were originally disappointed with the sound level.Well I didn't know that! Does that have any effect on the navigation?