when i bought my 98 gt over the summer, the guy had put in an aftermarket pioneer head unit, and had taken out the mach 460 amps and put in a boss audio amp with rockford fosgate subs. well i didnt want that mess, so i took it all out, and couldnt get any bass. so my buddy just took out his 460 amps cuz he wired his aftermarket straight to each speaker, so i bought them and plugged them up, i do notice more sound coming from the rear speakers, but still no bass! anything close to bass is very crackily and nasty sounding...help! i dont know anything about car audio!... :hammer: