DR with 450V on the plates. Problem?

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by kiteflyer, Sep 6, 2006.

  1. kiteflyer

    kiteflyer Member

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    My 67 deluxe reverb seems to run the tubes pretty hard at 450V. I haven't had any problems with tubes overheating (brimars and JJ's seem to be handle it ok), but I'm wondering if this is a problem that deserves attention. I definitely don't want to do any major mods, but it seems to be a little out of whack...

    Opinions or suggestions? thanks!
     
  2. bob-i

    bob-i Member

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    No that's about right for a BF or SF Deluxe. I just completed an amp built using a Deluxe vintage style xformer and I'm getting 440V, very close. You're right that you need rugged 6V6's to handle that voltage. JJ's and the new EH's seem to be fine as long as you keep the bias in line. They can handle the voltage but I'm not so sure about the total dissipation.
     
  3. Blue Strat

    Blue Strat Member

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    That's a bit high, but good 6V6s tend to handle it.

    A possible mod to consider is having Ted Weber (www.tedweber.com) cook up a Copper Cap with 5U4GB Zener and GZ34 sag.
     
  4. mbratch

    mbratch Member

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    My '65 BFDR reads around 440V with JJs when biased close to the 14 watt peak (or about 9.8 watts RMS) power spec. With modern Tung-Sols it comes in around 430V or so with a similar bias adjustment. Haven't had any problems.

    The original Fender schematic says 415V +/-20%, which would be a range of about 335V to 495V if you take it literally.
     

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