5f4 / 5e7 build

Discussion in 'Shock Brother's DIY Amps' started by theprofessor, Feb 2, 2019.

  1. King Fan

    King Fan Friend of Leo's

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    hmm see below
     
    Last edited: Oct 11, 2019
  2. King Fan

    King Fan Friend of Leo's

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    Benvenuto, amico. :)

    You're right, good eye... those small upgrades and updates are all potentially useful.
    • Adjustable bias -- a very useful, convenient way to help you set your amp to run 'best.' Not a mod to the original sound, but a modern way to avoid having to replace resistors to set the all-important power tube bias to save your tubes and get the best sound.
    • Rectifier diodes -- these are simply protection against possible tube failure damaging your circuit. Easy, minor, and definitely will not alter the sound.
    • The 470R 'screen resistors' from pin 4 to 6 on the power tubes are an 'update' that adds protection and may improve the overdrive tone.
    • If I'm seeing right, the 1.5K control grid resistors connect to the 220 K either way. Recall pin 6 in inactive in these tubes, so that lug is just a tie point. Tying it to pin 6 is probably more physically stable than hanging it in the air.
     
    Paul-T likes this.
  3. ginomolinari

    ginomolinari TDPRI Member

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    Grazie!
    Ok, think I’ve got the gist. But I cannot see from the updated layout what kind of diodes are used and the pins to connect them to. Can you shade some light?
    Thanks.
    i am ordering some missing parts and I will start a new tread on my build. Hopefully it wont look too amateurish. :)
     
  4. King Fan

    King Fan Friend of Leo's

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    For the diodes, and in fact all the items we discussed, you can hunt up good info on Rob Robinette's amazing pages, especially on 5e3 and 5f6a mods.

    upload_2019-10-11_15-2-44.jpeg
     
    BigDaddy23 likes this.
  5. BigDaddy23

    BigDaddy23 Tele-Meister

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    ^ This.......

    Rob's pages explain all of those tweaks and are immensely useful to any amp builder.
     
  6. ginomolinari

    ginomolinari TDPRI Member

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    Thanks guys. I have been reading alot on his website. I didnt think those mods were compatible with different amps. I guess I have a lot to learn.
     
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