The previous owner of my 2010 2.0 roadster had told me that the original subwoofer amp died, and he replaced it with a similar Rockford Fosgate unit. So tonight I poked my head under the passenger side of the dash, and sure enough he did a nice install of a pretty slick little amp for the sub. I tweaked the gain and crossover settings to my liking, but now I'm confused about one other thing... Where the heck is the main amplifier for the full-range speakers? There's clearly a high-pass filter enabled downstream of the JVC head unit, since even with the crossover settings disabled on the head unit, there's still zero bass coming from the main speakers. The sub fills in nicely, but being able to adjust the high pass on the mains to allow for a little more bass through them would be REALLY nice. Can anyone point me in the direction of how to access the main amplifier? Thanks!