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Mods to Super Reverb (please comment!)

Discussion in 'Shock Brother's DIY Amps' started by richon, Aug 17, 2010.

  1. richon

    richon Tele-Meister

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    Hi , this is my post to the project i'm about to start

    a ONE CHANNEL with reverb , NO vibrato/tremolo, Super reverb Clone

    Please look at the picture of the schematic and comment the following questions:

    1.- Normal Channel not conected: V1A and V1B plate resistors not conected
    2.- bypass cathode resistor of V2B (recovery of EQ in Vibrato channel) changed to 1,5K
    3.- No vibrato connected
    4.- 220K mixing resistor (and 0.1uf after reverb recovery) omited
    5.- V4 (reverb recovery) conected directly to the 0.001uF coupling cap in the PI

    6.- in the bias section, should the 2,2M resistor (inside the green box) be stil used (to avoid building the vibrato section)?


    thanks, I'll post more of it as we keep on building it together.
     

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  2. laird

    laird Tele-Holic

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    That all looks correct to me. I think that #6 (the 2.2M resistor) can be omitted - it's used to create a high-impedance load for the oscillator, it shouldn't affect biasing at all.

    Since you're doing a scratch build, how about replacing the 1M input grid resistor on the reverb driver with a 1M pot? This will give you a reverb dwell control.

    -Laird
     
  3. richon

    richon Tele-Meister

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    excelent,... i'll post a revised new Schematic with all mods available.
     
  4. richon

    richon Tele-Meister

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    Now this shows my mods :

    No vibrato connection
    Bias without vibrato part
    Cathode resistor of V1B
    Maybe Reverb Mixer mods




    now, How obligatory should a Tube Rectifier used on this amp?

    why not a simple Diode Rectifier?
     

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  5. backalleyblues

    backalleyblues Friend of Leo's Silver Supporter

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    Richon,

    Tube rectifiers create a nice sag when pushed, one of the reasons we love Super Reverbs up loud... you can also change it easily over to SS rectification using either a copper cap (from Weber) or some sort of plug-in for that socket, like what the Bassman re-issue had when it first came out.

    If you're going to modify the reverb controls, you might as well go with a complete 6G15 reverb unit, ala Vibro-King... it IS a scratch-build, why not?

    Franc Robert
     
  6. richon

    richon Tele-Meister

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    yes, I was thinking of adding some controls more to the reverb section (as I allready have a 6G15 reverb unit that I like a lot)

    My 5E3 amp, has no Rectifier tubes and compresses a lot also...

    so, should I also add a rectifier to the super, or it would be as a tinny Twin reverb with SS rectifier?
     
  7. laird

    laird Tele-Holic

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    I'd build it to use a tube rectifier. You can plug in a Weber copper cap (which emulates the voltage drop and sag of a tube rect), a straight SS recto (Groove Tubes has one), or go with the real deal. Just be aware of the big B+ increase with a straight SS recto- expect B+ to jump 30v.

    -Laird
     
  8. richon

    richon Tele-Meister

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    I was planning on building (ask a friends factory) to wound a special Power Transformer to have the Voltages ok, even when using SS rectifier (like another amps i've build) to avoid using the amp with too high plate voltages

    Besides this, right now i'm wandering how to set the bias pot and voltages connection to have the right bias on my amp.
     
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