Are 6l6GC/7581A/KT66 interchangable? For an Ampeg PF-50t

Discussion in 'The BASS Place' started by ColdEye, Sep 21, 2021.

  1. ColdEye

    ColdEye TDPRI Member

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    Looking to change the power tubes on my Ampeg PF50t, they take 6l6GC, Can I only use those or can I use a KT66 or 7581A? Sent an email to Ampeg but no reply yet.
     
  2. Timbresmith1

    Timbresmith1 Tele-Afflicted

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    KT-66 draw more filament current. If the pt can handle that, it’s a fine swap if the bottles will fit.
     
  3. Denton

    Denton Tele-Meister

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    7581a yes. Not sure on the kt66. Unless you have a sweet pair of NOS 7581a GE, the new TungSol are good.
     
  4. JRapp

    JRapp Tele-Holic

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    Nyet on the KT 66---more current draw, for one thing.
    7581A is a nice upgrade from 6L6GC if ya wanna little more headroom and fidelity. And yes, the Tung Sols are pretty good.
     
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