Power Amp Repair

Thanks i really apreciate your help, my problem i think was caused because an excesive input signal, i connected the cpu output directly with the input of the amp, so always was working with constant cliping in 8ohms, the fuse blows and when i open the amp the input phase was carbonized, so i change it for a new one with the seller, now i use a mixer but i encounter some problems, the fuse still blows, i had constructed a gx-300 clone with the exact components and works fine, but i still have the fuse problem in the clone.