2 prong to 3 prong ground wire conversion question...

Discussion in 'Ampage Area' started by erlomd, Apr 12, 2021.

  1. Archtops

    Archtops Synchromatic

    525
    Mar 4, 2021
    SoCal
    Sorry I’m late to the gig but welcome erlomd!
     
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  2. erlomd

    erlomd Electromatic

    17
    Apr 12, 2021
    Miami, FL

    IT WORKED!!!!

    the added resistor on the preamp tube killed the noise! now it’s sounding great! Thanks again guys for all the help and insight.

    Now I have to find a way of killing the noise with my pedals! Hahaha (it’s never ending Huh?)
     
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  3. hcsterg

    hcsterg Friend of Fred

    Feb 13, 2012
    France
    Fine @erlomd ! :cool::cool::cool:

    Yes, It's a very simple modification which is very efficient - the compulsory tip is to place the balancing resistors "at the feets" of the first preamp tube, the one which deals with the lowest signal level.

    The nec-plus-ultra is to use a potentiometer instead of the two Rs, in order to fine-tune the cancellation of the hum. I do this on big amps, with gain, but it can be done on any model. It was notably done on SF 100W Twin-Reverbs, but not on BF ones... :D

    Did you also tested the adjustable bias modification ? o_O

    A+!
     
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  4. wabash slim

    wabash slim Gretschified

    Age:
    71
    Feb 10, 2010
    lafayette in
    Batteries.
     
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  5. erlomd

    erlomd Electromatic

    17
    Apr 12, 2021
    Miami, FL

    Oh man, using a pot to fine tune the hum sounds amazing! I would try that but feel queasy drilling a hole on my bassman!
    As for the bias knob... Not yet. Thats next on my "to do" list.
     
  6. erlomd

    erlomd Electromatic

    17
    Apr 12, 2021
    Miami, FL
    I'll give that a try. Im running a Strymon Riverside for my overdrive. Thats obviously the pedal that causes the most hum. And obviously the more pedals I switch on, the more the noise..... but even when I have all 4 of my pedals turned on, its not nearly as annoying as what the amp was doing before.
     
  7. wabash slim

    wabash slim Gretschified

    Age:
    71
    Feb 10, 2010
    lafayette in
    The other thing to watch for is not to run signal lines along with AC. Cross at 90 degree angles only. Poor quality signal cables could be an issue as well. Stray AC is another problem, Motors, neon and fluorescent lights, appliances, and computers can all generate noise.
     
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  8. erlomd

    erlomd Electromatic

    17
    Apr 12, 2021
    Miami, FL
    So I figured out that the Strymon does not like to be Daisy chained with the other pedals. So I purchased a single power supply just for the strymon and plugged it in to a separate outlet. And BINGO! no more noise!
     
    Henry likes this.
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