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Variable Resistance on your B+ Line?

Discussion in 'Shock Brother's DIY Amps' started by kleydejong, Oct 19, 2020.

  1. kleydejong

    kleydejong Tele-Holic

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    I watched a video today from Rick Beato:



    You may certainly draw your own conclusions on the tone clips and EVH lore. Rhett certainly expressed that he could feel the change in voltage. From a technical perspective it would seem to me that it is a powerful tool for changing the way the tubes bias and generate load lines.

    I was thinking a bit on that concept and came up with this idea. What about introducing an L Pad variable resistor in the B+ line? Before node 1 sends to the power tubes would be most powerful / impactful, but I'm a bit leery about that messing with bias and tube life and amp stability in the power section. So what about after the first node sends to the OT - then a choke - then you run a bit lower resistor, maybe 2.2k in series with an L Pad of maybe 25k to 50k? The 12AX7's seem pretty robust to handle a change in voltage.

    Anyone tried this or seen it? Worth exploring?
     
  2. kleydejong

    kleydejong Tele-Holic

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    [​IMG]

    A mockup of what I'm thinking just as a potential example.
     
  3. tubegeek

    tubegeek Friend of Leo's

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    Look into VVR (variable voltage regulator) - that's the more modern way to implement what you're talking about.
     
  4. kleydejong

    kleydejong Tele-Holic

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