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    KT66 vs 6L6GC NOS Tubes


    Ed Cheek

    Posts : 6
    Join date : 2013-02-10

    KT66 vs 6L6GC NOS Tubes

    Post by Ed Cheek on Thu Feb 14, 2013 7:31 am

    Hello all,

    I would like some of you folk's advice from experience and knowledge. I have a newly built ST-70. I am buying a set of Gold Lion KT66 tubes to try. I also have an opportunity to buy a quad of NOS GE 6L6GC tubes. Would it be worth using the NOS tubes versus the new KT66 tubes? Does anyone use NOS 6L6GC tubes or have you used them? What is the difference in performance? I would expect the NOS American tubes to last longer.

    Thank you all in advance.

    Ed Cheek

    Bob Latino

    Posts : 2382
    Join date : 2008-11-26
    Location : Massachusetts

    Re: KT66 vs 6L6GC NOS Tubes

    Post by Bob Latino on Thu Feb 14, 2013 10:25 am

    Hi Ed,

    You can use any 6L6 tube in an ST-70 amp be it a stock amp or a VTA ST-70 ..

    I believe that the maximum plate dissipation of most pairs of 6L6 tubes when used in a push-pull configuration is about 24 - 25 watts (per channel) while an EL34 is somewhat higher at maybe 35 - 40 watts per channel. Dynaco in their original ST-70 build manual mentions that you can use 6L6 output tubes in the ST-70. AFAIK you CAN use 6L6's in ANY ST-70 amp but you will probably lose some power from the amp. You may not even notice the slight power loss though ... Check out the link below from our forum here about an ST-70 output tube "shootout".

    ST-70 power tube shootout


      Current date/time is Mon Oct 24, 2016 10:07 am