Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Rockabilly1 on January 21, 2011, 12:12:27 am
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just recently replaced the tubes and blackfaced the silver out of it.
I'm getting a buzz when i turn the reverb knob up(reverb pan not connected)
there is also a hum, not sure if it is 120hz when nothing is connected to the amp.
the amp plays great otherwise. any help with the buzzes would be appreciated.
got the amp apart on my bench now
Thanks in advance
Oh yeah I replaced my filter power supply caps to all 16mf @ 450v caps
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The reverb will make noise when turned up and no pan attached. It's a free flying grid.
Same thing with the "nothing connected to the amp". In this case it's possible that the input jack is not grounding when the jack is removed. Does it make the noise with the guitar plugged in and the volume set to zero?
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yes it still does make the buzz when the guitar is plugged in and the amp is set at 0.
The reverb pot needs to be turned up a little to hear the buzz.
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Did you plug a reverb pan in? Or just ground the connection on the reverb return?
Guitar plugged in, Guitar set at zero volume?
How bad is the hum/buzz?
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sorry for the delay in the answer>
Either way if the pan is plugged in, guitar plugged or not it still makes a buzz.
I think it is 120 hertz. I just replaced the tubes and filter caps. I changed the filter caps underneath the chassis that are covered with the metal box all are 16uf I believe 450 vlts