Value and taper of volume pot in early SF master volume amps

Discussion in 'Amp Central Station' started by homesick345, Sep 20, 2021.

  1. homesick345

    homesick345 Poster Extraordinaire

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    Hey all. I'd like to know if Fender changed or messed with the 2 volume pots in its early master volume amps - say 73 twin or 75 super (not the high power ULs)

    My question is did Fender keep the value and taper of the channels pots the same, as in older non-master amps? (The normal volumes, not the Master)

    Finally what is the MOST tapered volume pot I could install on a super reverb , preserving vintage tone but with a very progressive feel. Thanks!
     
  2. Timbresmith1

    Timbresmith1 Tele-Afflicted

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    Okay, why?
    Why would a difference in taper matter? It’s just a number on a knob.
    On a guitar I can see not liking the taper because you might want clean at 7 and distortion at 9 and max distortion at 10; moving the control as needed during a song, and a given taper may or may not do that in a way you find useful.
    On an amp? Enlighten me.
     
  3. homesick345

    homesick345 Poster Extraordinaire

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    Volume jumping too quick.
     
  4. Timbresmith1

    Timbresmith1 Tele-Afflicted

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    There should be a code on the pot.
    It will be audio taper or reverse audio taper. Assuming the pot isn’t dirty, you’ll want the opposite of what is in there.
     
  5. Timbresmith1

    Timbresmith1 Tele-Afflicted

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    Looks like a 1 meg audio taper.

    So a 1 meg reverse-audio taper should do what you want.
     
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  6. kbold

    kbold Friend of Leo's

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    That's the first thought I had when homesick345 said " Volume jumping too quick".

    First thing I would do is get out the Deoxit.
     
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  7. Bob Arbogast

    Bob Arbogast Tele-Afflicted Silver Supporter

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    Fender often used 30% taper pots for the volume control. A 10% taper pot would ramp the volume up more slowly.

    I would imagine that a reverse audio taper would have the opposite result to what the OP is seeking.
     
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  8. homesick345

    homesick345 Poster Extraordinaire

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    You know where to get these? Thanks
     
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  9. Boreas

    Boreas Poster Extraordinaire

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  10. Bob Arbogast

    Bob Arbogast Tele-Afflicted Silver Supporter

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  11. Bob Arbogast

    Bob Arbogast Tele-Afflicted Silver Supporter

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    I think that most often a pot listed as Audio taper would be 10% (that's 10% of total resistance at 50% rotation of the pot wiper). I'm not sure where you would shop from Lebanon. This would probably be right:
    https://www.amazon.com/dp/B00P5F2V7K/?tag=tdpri-20
     
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  12. Mexitele Blues

    Mexitele Blues Tele-Afflicted

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    No way man.

    If the amp has J taper pots, then moving to audio taper pots will help with the fine adjustment. If it already has audio taper, try a lower gain 12AY7 tube in the associated channel.
     
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