GA-19RVT (sort of) clone. Questions

Discussion in 'Shock Brother's DIY Amps' started by NSB_Chris, Oct 24, 2021.

  1. NSB_Chris

    NSB_Chris Tele-Holic

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    I am considering implementing the preamp section of the GA-19RVT. The schematic that I find is:
    https://www.ampwares.com/schematics/gibson/ga19rvt.pdf
    Some things that I see often in Gibson amps is large plate resistors. I know that adds extra gain, but I don't recall what effect that has on the distortion character. Have to consult my amp books again.

    The thing I am interested in is the tone shaping between the first and second gain stages:
    Screen Shot 2021-10-24 at 7.14.18 PM.png
    The secton after C12 seems like it is intended to provide a little scoop in the tone. It seems to combines a treble pass with a low pass filter with a cutoff of about 220Hz. Then it has a variable low pass filter before the volume pot.
     
  2. muscmp

    muscmp Friend of Leo's

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    a lot of people call that the gibson amp tone sucking circuit and bypass it. it is a 3 legged rc circuit. they feel that bypassing it gets rid of the brightness that some gibson amps have.

    play music!
     
  3. ScottJPatrick

    ScottJPatrick Friend of Leo's

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