Ampeg Gemini bright and trem "afterbeat" switches

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by Trunkard, Dec 7, 2016.

  1. Trunkard

    Trunkard Member

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    Ampeg Geminis (at least I & II) have bright switches built into the treble pots to engage a bright cap and a switch on the trem speed pot to engage a trem "afterbeat" mode. The problem is, the switches only engage at the end of the pot's travel. So if you want the bright cap engaged, the treble must be all the way up, and same with the trem speed.

    If I replaced those pots with a pull switch type and wired it up the same way, would it work? It would be nice to have the bright switch engaged without the treble all the way up. I'm not sure how it would work for the trem, but maybe I could get the afterbeat effect at a slower rate?

    [​IMG]
     
  2. Jeff Gehring

    Jeff Gehring Silver Supporting Member

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    You could in theory do that. However, the treble pots and the intensity pot are all 4 meg pots -- a value that I seriously doubt you will find at all, let alone with pull switches on them.
     
  3. Trunkard

    Trunkard Member

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    That's a good point. Could I use a 5M pot and run 20M resistor in parallel to ground, essentially making the pot 4M?
     
    Last edited: Dec 7, 2016
  4. tele_player

    tele_player Member

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  5. Trunkard

    Trunkard Member

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    Right - edited my last post changing the Ks to Ms. The same principle would apply.
     
  6. Jeff Gehring

    Jeff Gehring Silver Supporting Member

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    Adding resistors in parallel donks with the taper of the pot, if that's important to you. Can you find a 5M pot with a pull switch? If so, just try that by itself...
     

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