CMATMODS Brownie question

Discussion in 'Effects, Pedals, Strings & Things' started by Deville2Rocket, Jun 23, 2008.

  1. Deville2Rocket

    Deville2Rocket Member

    Messages:
    1,112
    Joined:
    Apr 2, 2008
    Location:
    Riverside, CA
    Hello everyone.
    I read that the internal trim pot in the Brownie can be adjusted to change the tone of the pedal.
    What does this adjustment actually do?
    Thanks,
    D2R
     
  2. Axekisser

    Axekisser Member

    Messages:
    1,160
    Joined:
    Dec 16, 2006
    Location:
    Sunny Buffalo!
    It biases the last transistor (Q5). Optimally you would set the trimmer for 1/2 of the supply voltage (4.5vdc) but sometimes over or under biasing can lead to tonal changes. Go to the General Guitar Gadgets website and check out the documents for the BSIAB II. It's the same pedal. The information will explain what the voltages should be.
     
  3. jamison162

    jamison162 Supporting Member

    Messages:
    7,778
    Joined:
    May 15, 2006
    Location:
    FL
    Now you tell us...I saw it but never adjusted it. Sold it.
     
  4. erikm5150

    erikm5150 Member

    Messages:
    564
    Joined:
    Jun 8, 2006
    Location:
    Calgary, Canada
    the bias "should" already be adjusted by the builder.
    so there shouldn't be a need to adjust it.
     
  5. crzyfngers

    crzyfngers Member

    Messages:
    5,137
    Joined:
    Jun 7, 2008
    Location:
    texas (lots of edible animals)
    i took a beating for asking the same question about my java boost. DON'T TOUCH IT!
     
  6. Axekisser

    Axekisser Member

    Messages:
    1,160
    Joined:
    Dec 16, 2006
    Location:
    Sunny Buffalo!
    I guess I'm a "tweaker" so I never shy away from adjusting things!

    As for the BSIAB, you can get "starved battery" effects, underbias it for a thinner sound or over bias it for a "flabby" type sound. Kind of like adjusting bias on an amp. I find it helps to fine-tune the pedal for my rig. I slightly underbias mine for a thinner EL-84ish type sound. YMMV!!
     

Share This Page