Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: p2pAmps on June 20, 2021, 07:26:53 am
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This thread is meant for anyone who has either built a Hoffman PR or plans to build one. The veterans already know this stuff and more.
Consider the pictures and the ground bus for the signally side of things. These amps are fairly easy to get noise if you don't take care in your wiring and ground schema. I have personally found that this model has worked best for me and I have built a large number of these amps with Doug's layout. I do add my own little twists and turns but the basics are the same.
Cheers,
Mike
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Good looking amp. You continue to set the bar high.
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Beautiful build.
I'm always looking for better management of my heater circuit layout. It appears (but I can't quite see this in your pics) that you run your heater wires from the PT directly to the pilot lamp housing, and use the lamp lugs there to tie both the artificial center tap and your 18AWG to your heaters. Correct?
Seems like a good idea to use an "out of the way" location on the chassis for that purpose. I have been installing small terminal strips close to the output tube closest to the rectifier for this purpose, but your method may be more efficient.
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That's the way Fender wired many of their amps. The originals have a bias board located near the pilot wire, so the look is not as neat and clean as p2pAmps though.
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Beautiful build! I always enjoy looking at your handiwork; always very neat and tidy. :thumbsup:
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Beautiful build.
I'm always looking for better management of my heater circuit layout. It appears (but I can't quite see this in your pics) that you run your heater wires from the PT directly to the pilot lamp housing, and use the lamp lugs there to tie both the artificial center tap and your 18AWG to your heaters. Correct?
Seems like a good idea to use an "out of the way" location on the chassis for that purpose. I have been installing small terminal strips close to the output tube closest to the rectifier for this purpose, but your method may be more efficient.
Hi There and thanks.
So the heater wiring is pretty standard stuff so I cannot take any credit for that part. The wire is 18AWG for sure. As far as the artificial center tap goes, I usually hang that off the pilot and make a little wire extension so I can ground on the star where all the power section is grounded. The ground buss is where all the signally stuff is grounded, like cathodes, pots etc. The contact point is right under the inputs. So far I have found that to be a dead quiet solution and it also gives me a nice place to loom the wiring that goes up front. Also make it easier to service pots in the future if need be. Right or wrong that's the way I come to do things. Lord knows I have a lot to learn still :)
Mike
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It could have all been catastrophic had it not been for the fine selection and very cool use of the green zip ties. P2PAmps has this creative artistic flair and each amp I have seen of his are somehow sometime use of capacitors, covering leads with teflon.
You do set the bar high!
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It could have all been catastrophic had it not been for the fine selection and very cool use of the green zip ties. P2PAmps has this creative artistic flair and each amp I have seen of his are somehow sometime use of capacitors, covering leads with teflon.
You do set the bar high!
Checks in the mail Ed!