Taking out 2 power tubes out of 4 (EL84)??

Discussion in 'Amps and Cabs' started by asintoras, Sep 10, 2008.

  1. asintoras

    asintoras Member

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    Hi folks,

    I own a Gibson Super Goldtone GA30RV made in 2001, which was designed and made in UK (Trace Elliot).
    I have been told that with some particular amplifiers you can take out some of the power tubes (2 tubes out of 4 tubes in the power section) in order to reduce power.

    So I have a question:
    Is that possible to do with this Gibson amplifier (it has 4 x EL84) without any harm to it?

    By the way, it's a shame that the production of those wonderful amps cames to an end. They're great!

    Thanks, and I'm looking forward to hear from you guys.:munch
     
    Last edited: Sep 10, 2008
  2. asintoras

    asintoras Member

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    No one knows about it?
     
  3. Blue Strat

    Blue Strat Member

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    I don't know about that particular amp, but most EL84 amps are cathode biased. If yours is and the power tubes share cathode resistors, pulling out a pair will cause the remaining pair to run EXTREMELY HOT and burn them out quickly.
     
  4. s2khawk

    s2khawk Member

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    yes yes yes to what Blue said, I run 2 84's in a 4 tube amp all the time BUT that amp has a half power switch where the cathode bias actually changes to fit 2 tubes correctly.
     
  5. asintoras

    asintoras Member

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    Yes, the amp is cathode biased, so let's forget about that idea.

    Thank you guys!
     

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