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Serious treble attenuation with RobRob PPI MV. Is that your Experience?

Discussion in 'Shock Brother's DIY Amps' started by randomhitz, Feb 15, 2021.

  1. randomhitz

    randomhitz Tele-Meister

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    Did I screw up somehow? Pretty simple mod. Seems like it's creating a filter.
     
  2. Tom Kamphuys

    Tom Kamphuys Tele-Holic

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    What amp? Schematic?
     
  3. randomhitz

    randomhitz Tele-Meister

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  4. D'tar

    D'tar Friend of Leo's

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    Photos?
     
  5. Mexitele Blues

    Mexitele Blues Tele-Afflicted

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    I've always wondered, does PPI stand for pre-phase inverter or post-phase inverter?
     
  6. XTRXTR

    XTRXTR TDPRI Member

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    Also did you mod a Pre PI MV or a Post PI MV? "PPI MV" doesn't fully describe which mod you did. As others have said Photos and Schematic.
     
    Last edited: Feb 16, 2021
  7. Paul G.

    Paul G. Friend of Leo's

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    I have this on my 5E3. No, it doesn't effect the tone at all when turned down. Double-check all your work.
     
  8. David C

    David C Tele-Meister

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    I don't have any impact with treble attenuation with the master volume on my 5E3.
     
  9. randomhitz

    randomhitz Tele-Meister

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    Thanks for all your replies. Got it working properly. I'll school myself on how to post images. Seems like the only difference this time around was I had the proper I meg audio taper pot. Previously I was using a linear taper 1 meg while I was waiting for the audio one to arrive. I assumed the only difference would be which section of the travel would have the biggest effect.
     
  10. dan40

    dan40 Friend of Leo's

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    The pot taper should have no affect on the amps brightness. It may be that during the pot replacement you inadvertently fixed a bad solder joint.
     
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