63 tremolux w/ 6v6s question

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by inscho, Oct 3, 2006.

  1. inscho

    inscho Senior Member

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    I recently purchased a 63 blonde tremolux 6g9-a...which is wants an 8ohm speaker load...but instead of the intended 6l6s and gz34 rectifier, it is running 6v6s and a 5u4 rectifier....

    first off is there any dangers of running the amp in this way? the last owner was a respected amp tech in the area, but I would like to get a second opinion.

    2nd, with this tube setup...wouldn't the optimal speaker load be more than 8ohms?
     
  2. pitbull45

    pitbull45 Member

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    Tubes don't determine the load.
    Load is determined by the transformer
     
  3. erksin

    erksin Member

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    What difference does the tube compliment make regarding the ohm load? AFAIK, ohm load is determined by the transformer taps. I'm not saying you're wrong - just asking...
     
  4. inscho

    inscho Senior Member

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    couple folks at HC mentioned this....I haven't a clue, just wanted to get things cleared up.
     
  5. Blue Strat

    Blue Strat Member

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    Sorry no. Tubes determine the load and the transformer "transforms" the load.

    By switching from 6L6s to 6V6s, the output load doubles.
     
  6. inscho

    inscho Senior Member

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    so it being a 8ohm with 6l6s...it would be better to run it with a 16ohm cab?

    also is there any damage that could occur with these tubes?
     
  7. Blue Strat

    Blue Strat Member

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    From memory, I thought a Tremolux wanted a 4 ohm load (2 8 ohm speakers?). I just checked and there are 2 versions. Whatever, it's double with 6V6s.

    "Damage" would depend on the plate voltage and bias setting. 6V6s should be run at 440V or less on the plates, and about 20mA bias current.
     
  8. inscho

    inscho Senior Member

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    6g9 and 6g9-a are 8ohm, 6g9-b are 4ohm and all made after are 4ohm as well.


    I think I recall reading on FDP that the tremolux is run at 360v on the plates...but I really don't know anything about that, does plate voltage vary between amps, or is consitent?...:(
     
  9. Blue Strat

    Blue Strat Member

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    Basically, you never trust internet hearsay or schematics when it comes to the safety of your vintage amp (or yourself)...you measure it.

    One schematic I looked at says 360, but that schematic was drawn when line voltage was 110. Today it's 120, so figure 10% higher plus extra when you use 6V6s (biased correctly) as opposed to 6L6s. Hence, MEASURE IT WITH 6V6s to be sure.
     
  10. inscho

    inscho Senior Member

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    ok will do, thanks for your advice! :)
     
  11. redtoploader

    redtoploader Member

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    Whats the # on the output transformer?
     
  12. jcs

    jcs Member

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    i have a 6g9b tremolux it says 117 volts on the chassis and i think it is a 1964 built amp with 125a6a (4 ohm) tranny..

    from what i have gathered,these amps are known for having low plate volts and thus not much headroom and darker-saggier in tone..

    compared to my 62 bandmaster which has a ss rectifier and bigger power tranny though both share the same output tranny(125a6a or 125a7a are the same only the impedance is different),the result is the bandmaster is a bassier punchier tone with the bandmaster and very quick response and more headroom...

    plus the bandmaster has a presence knob where the tremolux does not..
     

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