FireFly type cascade gain

Discussion in 'Glowing Bottle Tube Amp Forum' started by radiocaster, Jul 30, 2018.

  1. radiocaster

    radiocaster Poster Extraordinaire

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    Is there any other amp that uses this design?

    Please do not say Marshall or Fender, I've never seen them have a plate going straight into the cathode of another triode.
     
  2. clintj

    clintj Friend of Leo's

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    That's a cascode stage, and seems to be a bit of a rare bird. It's idea is to emulate the gain and feel of something like an EF86 pentode without the microphonics and other issues, or having to scrounge for a good NOS tube.

    I can't think of anything other than some really oddball designs that used one, but they have a little bit of a cult following in the DIY/homebrew amp builders world.

    More info here:

    http://www.valvewizard.co.uk/cascode.html
     
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  3. radiocaster

    radiocaster Poster Extraordinaire

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    I've seen this design in a couple of places on the net, in reference to transistors though.
     
  4. Inglese

    Inglese Tele-Meister

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    It's hard to find in guitar amp because Fender never used it! Thus is rare in all the copies of a copy of a copy...
    More common in HiFi design.
     
  5. Deepblankspace

    Deepblankspace Tele-Meister

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