[89CamaroRS]

ok, i'm a total moron when it comes to electronics so any help u guys could offer would be greatly appreciated. i just installed 2 10" pioneer subs in my car powered by a 300 watt jensen amp. (not real expensive stuff) they hit extremely hard for about 3 days then the ground cable came off when i swerved to miss an a****** that pulled out in front of me. if blew the fuse in the hot line from the battery. i replaced the fuse and now the subs dont hit for s*** and low tones sound extremely broken up. the amp's power light is on and i haven't changed any of the settings. i've checked all the wires too, everything seems to be ok. could i have damaged the amp so that the subs r now underpowered? i was under the impression that amps either worked properly or didn't work at all(please correct if wrong). or could it have something to do with the old battery in the car? (it would stall at idle before if the box was cranked.) it's a brand new pioneer head unit too. any ideas?

thanx guys,
Will