Galien Krueger 800RB blows main fuses

[david maurer]

On a Gallien Krueger 800rb bass amp, if the main fuses blow by just tunring on the power switch, what is the most likely cause?

[Enzo]

Same thing it is in any amp that blows fuses. Shorted output devices or shorted power supply rectifiers. With the amp cold, check for E-C shorts in all output transistor strings. Check the main bridge for shorted legs. That should cover 95% of the time. beyond that, try the usual suspects - Shorted filter cap, some sort of short across the power rails, some sort of short across the output, shorts acrosss the primary. And of course loose hardware - any missing screws or nuts? A loose one under a pc board can short out most anything.

[david maurer]

Thanks for your quick response. Found shorted rectifiers in the power supply section. The caps don't look too good either. That may be the real cause of the failure. I will change them too. Appreciate the help.