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

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

  1. asintoras

    asintoras Member

    Messages:
    1,427
    Joined:
    Oct 26, 2007
    Location:
    Exeter, Devon - UK
    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

    Messages:
    1,427
    Joined:
    Oct 26, 2007
    Location:
    Exeter, Devon - UK
    No one knows about it?
     
  3. Blue Strat

    Blue Strat Member

    Messages:
    30,063
    Joined:
    Aug 2, 2002
    Location:
    Sterling, VA (not far from Washington DC)
    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

    Messages:
    381
    Joined:
    Oct 14, 2006
    Location:
    dropped to 3rd drunkest city in US
    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

    Messages:
    1,427
    Joined:
    Oct 26, 2007
    Location:
    Exeter, Devon - UK
    Yes, the amp is cathode biased, so let's forget about that idea.

    Thank you guys!
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice