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will changing resistors in the gain stage raise gain?

Discussion in 'Amps and Cabs' started by j2b4o, Dec 23, 2009.

  1. j2b4o

    j2b4o Member

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    if I put a resister that allows for more current would gain increase? seems like it should but Im still getting my feet wet with amp moding.
     
  2. epluribus

    epluribus Member

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    Barring a good electronics course like US Navy NEETS (free online) you might check the tech articles at Randall Aiken's place, Tales From the Tone Lounge, and an old TGP thread on the subject.

    All that said, without a pretty solid understanding of tube circuits, although you can alter the gain structure of a gain stage, you're going to be fairly limited on tuning it for the specific behaviors you like. Even so, it certainly is terrific fun!

    One last word, for all of our readers...Don't open that chassis if you don't know how to drain the residual power properly! No kiddin' here, they contain fatal voltage levels even when unplugged for long periods of time!

    Happy solderin'!

    --Ray
     
  3. j2b4o

    j2b4o Member

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    thank you kindly! Im not new o soldering and always carefully discharge the am before doing anything. I have modded a few of my pedals and a few guitars. just wondering what the main culprit controlling gain level.
     
  4. Marble

    Marble Member

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    If you lower the resistance you probably will increase the plate voltage which will end the lives of the tube quicker, and if they're old tubes with serious tone, you probably want to preserve those as much as possible.
     
  5. j2b4o

    j2b4o Member

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    found a thread where someone with the same amp switched a cap from 22uf to 470uf and the corresponding resistor from 1.5k to 820 ohm 1/2w resistor in the pre amp and it raised gain considerably.
     
  6. hasserl

    hasserl Member

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    If you're serious about this, post a thread in the Amp Tech section, and give specifics about what amp is involved, a link to a schematic if possible, and the guys there will give you advice on the project and help you understand what it is your doing.
     
  7. mark norwine

    mark norwine Member

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    Amps have lots of resistors. They all do different things.

    Do you have a particular resistor in mind?

    Yes, thats a pretty general response.....but your question is fairly general, too.
     

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