So i tried to install a sub in my 06 g35 coupe and i got it working and i think the amp i was using was to over powered cause the sub could only handle 400 watts and i used a 1200 amp watt and then all my speakers stopped working. one of my friends suggested that maybe the stock amp fuse stopped working but i really dont know whats wrong can anybody help me

 

Try posting this in the tech/audio visual section, you'll get more help there