1202-84 OT on JTM100 Super PA - EL34 or KT66

Discussion in 'Let's Talk Vintage' started by VanillaGorilla, Sep 26, 2021.

  1. VanillaGorilla

    VanillaGorilla Member

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    A friend of mine is selling his 66-ish Super PA 100W JTM, right now it is equipped with EL34s, it has the 1202-84OT. Did it come stock with EL34 or was it a KT66 Amp from the factory?

    Thank you, Ben
     
  2. Seanxk

    Seanxk Well-Known Member

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    As far as I know the 1202-84 was for use with KT66 and had an primary impedance of 4K, I'm not entirely sure but someone will be along soon hopefully. Let's hope it hasn't done any damage.
     
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  3. neikeel

    neikeel Well-Known Member

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    In my experience it should be running KT66s as it has z of 4k which matches the 8k that a two cylinder JTM45 runs. An EL34 amp for 4 tubes @ 100w be 1.7-2k primary impedance. You can run EL34s but they will not give you full power - you would need to run a half step mismatch on your load for that ie use 16ohm selector for 8ohm load.
     

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