well i put my wifes bazooka mono block amp in my car and i had to change the fuse set up from 30 amps to 60 amps well i had just a 30 amp car fuse on my old amp but i put in a agu fuse and holder and my old amp got really quiet so i put in the bazooka and it still quiet why? its a 375 rms amp it should be really loud my old amp was a 350 max an dit wa smuch louder then this bazooka amp. why did it get quiet after i changed the fuse style.

I've never heard of a fuse change affecting the output of an amp. Here'* a far out guess though. If the new fuse holder/fuse combo had some crazy resistance to it, this would produce a voltage drop. To test this, use a multimeter and read the voltage from the + battery terminal to the begining of the fuse holder. Then measure from the + battery terminal to the end of the fuse holder. If there is a significant difference in voltage then this could be the problem. If crimp-on terminals were used then they may be suspects as well.

For the heck of it since you already have the multimeter out, measure the voltage from the +12v input to the ground input right at the amp. This should be very close to the voltage right at the battery. If not, there may be a ground problem as well.