This Peavey Classic 30 repair was a bit of a nightmare! It arrived with a fairly basic problem – the amp wouldn’t turn on. This was down to a loose screw. It held the mains fuse holder internally. When this came loose, the fuse holder was dangling in mid air and shorted mains directly to […]
Tag Archives | valve amp blowing fuses
If your valve amp blowing fuses, there are a number of possible causes. If your amp blows a fuse, it’s almost always for a reason, so make sure you get somebody to investigate.
The most likely reason is a dead power valve – a 6L6, EL34, EL84 or 6V6.
Most valve amps with EL34s or 6L6s must be re-biased when (see bias page) you change the tubes. Some cathode biased amps can be replaced with a matched set without re-biasing.
Other possible causes of blown fuses in valve amps are valve rectifiers.
A short in a DC heater supply can also cause fuses to blow.
If you’ve got a valve amp blowing fuses, send me a message, I’ll be happy to take a look.
I’ve wanted to do a tubemeister repair since they first came out a few years back. I guess it’s a testament to general quality that this is the first to appear on the bench. I’m a big fan of the design aesthetic. 3 channels and a midi switching amp for £550ish is a lot of […]
My customer brought this Peavey Valve King repair in to me before Christmas to get an opinion on its state of repair. The amp was blowing fuses. The Valve King VK100 is a monster of an amp. Not fire breathing levels of gain like some Peaveys but a big and heavy brute with a classic sound. […]
A customer brought this fender repair to me with a common complaint. The valve amp was blowing a fuse every time the standby switch was turned on. A valve amp blowing fuses can be a number of things, but in this case I suspected that the amp probably had a faulty power valve. This turned […]
Marshall JCM2000 repair I get quite a lot of the JCM2000 series in for repair – both DSL and TSL. I think it’s because they were so popular, rather than any endemic issues. This particular JCM2000 is a TSL100, the triple super lead model. I’m writing the blog post quite a while after the repair […]
Marshall Repair This Marshall Repair was brought to me with one of those sneaky ‘hard to find’ problems. The amp was blowing fuses when the customer was playing it. He’d taken the amp to another repairer who hadn’t found any problems. Unfortunately the amp continued to blow fuses. Guitar amplifier repairs of this kind often […]
This Mesa Boogie Dual Rectifier Repair is one of the more unusual problems I’ve come across. The Mesa was brought in with very low (and unpleasantly distorted) volume and blowing fuses. I tracked the issue to the output circuitry and checked for all the usual failures with no result. The output transformer looked to be […]