Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: whoops on January 31, 2023, 09:06:12 pm
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Hello,we have a silverface Reissue (68 Custom) Deluxe Reverb Amp that is making some type of crackling noise.
It seems there's some rats inside the amplifier, I did a video showing the noise, if you guys could have a listen that would be great:
&ab_channel=MrCacciLLo
The Amp is relatively new, and it's well kept and taken care of.What do you guys think might be the problem?
Thank you so much
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Bacon and Eggs on hot pan during earthquake :w2: ( :laugh:)
Can you confirm that the "frying" is reduced/eliminated with REVERB control pot?
(There was a lot of traffic noise in the background)
Thanks and Regards,
Mirek
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1st thing to try is pulling out each tube, one at a time, to see if one of them is making the noise.
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Too much background noise.
Follow Tubeswell advice.
Did you check amp noise with nothing plugged to the amp ? It is a must
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RE pulling tubes, look at the schematic and start at the front end, and work towards the outputs. Don't bother pulling the phase inverter, output or rectifier tubes; you'd need to try replacements to troubleshoot those. Unplug your guitar & turn both volume controls, reverb and tremolo to zero. If it's quiet, then try each vol control, see if they're different, and move along with the other controls to see how they affect. If you can isolate it to an area, then you can swap 12AX7s from 1 channel to another. If this doesn't make sense, then take it to a shop, or study up on troubleshooting on Uncle Doug's youtube site or others for some simple amplifier basics. Good luck, and careful not to burn yourself on hot tubes!