New potentiometers for an early 90s AC30 TB6

Discussion in 'Other Amps' started by gilded, Jun 17, 2020.

  1. gilded

    gilded New Member

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    Hi, got an early 90s Korg built AC30 top boost amp.

    The potentiometers are a little dirty. I've tried cleaning them a few times. They say completely quiet for a few weeks, then start making noise again.

    I think I just wanna replace them and am wondering if anybody has an opinion about what the best replacement potentiometers would be?

    Thanks!
     
  2. South Park

    South Park Well-Known Member

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    CTS in audio taper work good you can get them on eBay
     
  3. gilded

    gilded New Member

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    Thanks, South Park. Appreciate your advice.

    I took a long look at the original pots. They are different from what I'm used to. I guess I need to look for some original replacement potentiometers. The brand is Omeg, description is: 470K, Log B, Dshaft; something like that.

    Does anybody know a source for these Made in England pots?
     
  4. South Park

    South Park Well-Known Member

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    You just have to match up the shaft length so the knobs all look the same you might want to replace all of them . Ebay and tube amp parts supply have them . Is it board mounted
     
  5. neikeel

    neikeel Well-Known Member

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    You will struggle to get D-shaft type pots, you will be able to get 470k with the correct shaft diameter (measure accurately) but you may well need to cut them to length and then file a flat at the right place for your set screw to sit. This can be a real PITA and you must tape them up to avoid swarf getting into the pot either through holes in the back or down the spindle.
    If it says B that is normally designated a linear - not logarithmic pot which are A type. If they are C type that is reverse log.
     

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