Hello UG,

I already made a thread on this issue found here ,
yet there have been a lot of changes now, so I figured I'd remake it.

So, every now and then, when I put my amp on standby, let it warm up, and turn it on, it makes a very loud buzzing noise. This eventually stops after trying it again a bit later (15-30 minutes).
I've had my uncle, who's an electrician, check the grounding, and he said there is no problem with it.
So far, I haven't had this problem on any other place.

Do you guys think it's an amp issue or any other electrical issue?

#2 of the Orange TH30 Clique
Orange TH30 Head
Orange PPC410 Cab
Ibanez ART500e
Cort KX5
Almansa 434 Cedro
Last edited by Bauwke at Sep 13, 2011,
^ your link does not work FYI

but I found your thread:


honestly - I'd just bump the original thread. Cathbard posted in there so he's more likely to see it if he's already posted in it. He is a lot smarter than I so I don't have much else to offer outside out of the fact that you may have an overly microphonic preamp tube or a tube pin arc'd with the circuit board.

I'd check all the tubes, spray the pins with contact cleaner and make sure all the tubes are seated (pushed down) real well.
In addition to the advice in the other thread I'll throw out something else. I'd had several amps that had one or more of hissing, popping, and volume drop outs that had the same problem. They all had cracked solder joints between the jacks/pots and the circuit board. This required disassembly to the point where I could reflow the solder joints.

You may not see the cracked joints without a magnifying glass, so I just reflowed all the jacks and pots.

I also had a friend's amp that did the same exact thing and I traced through the whole amp's circuit before it led me to the problem. Someone had checked the high voltage fuse and when they put it back they didn't engage the locking cap on the fuse. So the fuse was loosely coupled to the contact in the fuse holder. The amp would work fine then intermittently lose volume.
Last edited by fly135 at Sep 13, 2011,
I guess I'll have the amp checked out at a music shop, and if I can rule out the amp look for issues with my house's electricity?

#2 of the Orange TH30 Clique
Orange TH30 Head
Orange PPC410 Cab
Ibanez ART500e
Cort KX5
Almansa 434 Cedro
Did you try cleaning the tube sockets like I suggested?
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