Okay, I have Stock Speakers, with a Sony XPlode 4x55W aftermarket head unit, nothing to special. I want more bass, but only have a $500 budget. I don't mind running cable, taking out seats etc to install myself. But for better sound, with more bass on a $500 budget what would you guys reccomend?

I've heard that a good set of 6x9's with the right Amp can put out quite s good amount of Bass, which might be a good idea as I don't really want a big ass Box in the back if I can help it.