Princeton Reverb Build #3

Discussion in 'Shock Brother's DIY Amps' started by Phrygian77, Jun 26, 2019.

  1. tubeswell

    tubeswell Friend of Leo's

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    Try increasing the 22k to anything between 27k and 56k and see where the bias voltage lands. You’ll end up with more negative voltage, but the higher you go, the less adjustment range the pot will give you (but that’s not necessarily a bad thing).

    Also, What voltage rating is on the bias supply cap? (You want about 2x what you might need to be on the safe side)
     
  2. Phrygian77

    Phrygian77 Tele-Afflicted

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    It's a 100uF/100VDC. PT is a Classic Tone 40-18027 (630VAC secondary) with a Sovtek GZ34. Like I said I've had plenty of range with the JJs so far. Using a 5U4GB probably would have made this work out fine, and put the voltage a bit lower where it really should be for those tubes. The more of these I build, the more I'll tweak. 27k is probably a better choice.
     
  3. Phrygian77

    Phrygian77 Tele-Afflicted

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    By the way, I had been using Murata MLCC X7R caps for the tremolo oscillator. The Xircon caps from Hoffman fit nicely into my custom board layout, and they have thicker leads.
     
  4. No457 Snowy

    No457 Snowy Tele-Meister

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    Nice build, I really like the quality of the solder joints, that's how they should look.
     
  5. D'tar

    D'tar Friend of Leo's

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    Fantastic AGAIN!!! You do great work Phryg! Thanks for sharing. Watching out for #4.
     
  6. King Fan

    King Fan Friend of Leo's Ad Free Member

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    Yep, gorgeous, superb build!


    Sent from my iPad using Tapatalk
     
  7. Phrygian77

    Phrygian77 Tele-Afflicted

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    I try my best to get optimal wetting, and keep everything still as it cools. That's what's critical. All of it was done with a Weller WLC100. It's cheap and it works great.

    Thanks guys! I don't know that there will be another #4 PR anytime some. Next up is a Vibro Champ (or two). Just ordered a cabinet for it this weekend. I also still have a brown Super cabinet and chassis to work on, and a quad 6V6 Super Lead to build.
     
  8. FenderLover

    FenderLover Friend of Leo's

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    Cool!
     
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  9. Phrygian77

    Phrygian77 Tele-Afflicted

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    I have pretty much everything for it except a cab. I'm kind of dreading it because I'm doing it with Topcoat wire and turret board, which is a first for me, but I want it to look like a Marshall build.
     
  10. Phrygian77

    Phrygian77 Tele-Afflicted

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    Also, that build will be in 100 watt chassis with 50 watt iron. It should be able to run a quad of 6V6s, a pair of EL34, or even a just pair of JJ 6V6s with the appropriate reflected impedance.
     
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