Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: fdesalvo on March 01, 2022, 12:13:35 am
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Hi, all.Happy Monday. I'm almost finished debugging a customer's 6G2 clone and am down to two remaining issues:
1. Buzz when volume at 0 - 2 + tone at 0-9 or when volume is at 10 and tone is set anywhere below 10. Buzz comes on and off like a light switch when moving volume or tone control.
2. Non functioning trem
My main concern is issue #1 at the moment. I found and corrected a host of assembly errors and now the amp is nearly silent, save a little hiss at volume, but there's buzz aplenty when the conditions of #1 are met. I can nearly silence it by touching V1B's grid wire with my finger. After running shielded cable here, no improvement was noted. Layout is mainly old school fender with a hoffman ground bus scheme at the pots. All tubes good. Issue disappears with V1 pulled.TIA
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Picture of the pot wiring on volume and tone and picture of the chassis top view would be helpful.
Loose solder / bad solder joints?
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Look a bad wiring dress
Show good pictures of the wiring
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agreed on lead dress. the first amp I built is a 6g2, and I had a similar noise issue at 0 on the volume pot. fingers nearby the leads to the tube sockets would alter noise characteristics.
i simply moved them around with a chopstick until noise free, and ultimately cut and soldered new wire in place. i was using cloth covered solid core, fyi.
the tremolo wiring is a crazy antenna, had many issues to sort out before I got it working quietly and perfectly. all were lead dress issues, surprisingly. ymmv.
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I forgot to close this out apologies. Too many issues, so I did the most efficient thing and rebuilt it.