i bought and installed 4 new speakers(alpine spr 69-c for the rear 6x9 and alpine spr-17c for the front) for my 2008 g6 4 door sedan. and the drivers side speaker works just fine it has bass and clarity. but the other 3 speakers are just the music. no bass at all, even on the lowest of notes. I also have a JVC-KWXR810 headunit that has all the necessary adapters and what not. is it the monsoon's amplifier or something else? can anyone help me!?!