? for the tube gurus...

Discussion in 'Amps and Cabs [BG]' started by no4mk1, Mar 2, 2003.

  1. no4mk1


    Feb 21, 2003
    Seattle, WA
    I have an Ashdown EVO 300 with a 12AX7 in the preamp section.

    My father just gave me eight old tubes that he had in his basement (he is an old electronic engineer).

    I have a mixture of GE, Sylvania, RCA, Tung Sol, and Telefunken tubes. Some are 12AT7 and some are 12AX7 tubes. I also have a 12AX7A.

    Are these tubes interchangeable? Can I just try some in my preamp to see which sounds good?

    Some of these tubes look used, but some look absolutely pristine. Can I damage my amp trying one of these tubes, or will a bad tube just not work.

    The tube in my amp sometimes makes a "TING" "PING" sound that makes me think it may be going microphonic. So if one of these old tubes will be a sonic improvement, I would like to give it a shot.

    Thanks in advance.

  2. pkr2


    Apr 28, 2000
    coastal N.C.
    Yes they are interchangeable. Just pick the one you like the sound of best.

  3. Munjibunga

    Munjibunga Total Hyper-Elite Member Gold Supporting Member

    May 6, 2000
    San Diego (when not at Groom Lake)
    Independent Contractor to Bass San Diego
    Try each one and report back here. This should be interesting. At least one of those tubes ought to sound bitchen.
  4. Benjamin Strange

    Benjamin Strange Commercial User

    Dec 25, 2002
    New Orleans, LA
    Owner / Tech: Strange Guitarworks
    The GEs should be cool, as they are (were) American made and had better quality control at the factory. The 12AT7's won't have as much gain as the 12AX7's, but that may be cool for an active bass.
  5. no4mk1


    Feb 21, 2003
    Seattle, WA
    It ended up that I had 4 12AT7s and 4 12AX7s.

    I tried a Tung Sol, a Telefunken, and a GE.

    I couldn't get any sound out of the Tung Sol.

    The GE worked, but sounded kind of spongey. It wasn't very defined.

    The Telefunken sounds great! The sound is warm and defined. I'll leave that one in there for awhile and see what I think.

    The stock tube was a Russian made Electro-Harmonix.