I was moving my sub amp and unplugged all of the wires and when i was plugging everything back in the ground touched the positive wire that was already plugged in and i got some sparks this caused all 4 of the 30a fuses to blow so i ordered 4 more and when i went to plug them in the fuse sparked where i was going to plug it in causing it to blow again so i have 3 good ones i haven't put in yet. Anybody know what the problem is that is causing it to spark when i go to plug in the fuses?
If you have a completely disconnected amp and you connect ground and then connect +12V and it blows fuses, that amp is done unless the fuses are improperly rated or there are some cable remains shorting the speaker terminals or the power terminals at some place.
take the in-line fuse out of the power wire and replace the amp's fuses then replace the in-line fuse. If they still blow, you shorted something inside the amplifier when you let the positive and ground wires touch, and the amp needs to be repaired.
This is why you leave the battery's ground cable disconnected while working on audio gear wiring.