Modding Vox V847 into Volume Pedal

Discussion in 'Effects, Pedals, Strings & Things' started by sanders4617, Jan 7, 2008.

  1. sanders4617

    sanders4617 Member

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    Ok. I never use my Wah-Wah pedal. I have been thinking about buying a volume pedal, so I think I have heard of people modding their wahs into a volume pedal.

    Is there a way to do this? If so how?

    Also.. if its possible, I would like to make a switch to go from one to the other.

    I am not too good with reading a schematic and seeing what to do, I usually need some kind of visual whether it be in picture or just detailed words before I understand completely. If anyone can explain, please do so. I would appreciate it.
     
  2. GCDEF

    GCDEF Supporting Member

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    It would be easier to sell the wah and buy a volume pedal.
     
  3. Uma Floresta

    Uma Floresta Senior Member

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    I guess you could build some kind of simple clean boost and put that in there in place of the wah guts, and use the wah pot as the volume pot.
     
  4. Uma Floresta

    Uma Floresta Senior Member

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    Actually, there might be room for both - you could put a switch in there to go from wah to volume.
     
  5. Axekisser

    Axekisser Member

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    If I remember correctly, you just need to remove the cap that's across the inductor. Should be an easy mod. I have an old EH Crying Tone wah that can be used for a volume by turning a switch. I think the schematic is on line.
     
  6. Uma Floresta

    Uma Floresta Senior Member

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    Interesting!
     
  7. mistercoffee1

    mistercoffee1 Member

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    It's the cap that's labeled 4.7 uF.
    You can remove a leg (closest to the edge on the v847 circuit), or you can install a switch so you can have it in our out.
    [​IMG]
     
  8. Uma Floresta

    Uma Floresta Senior Member

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    I'm going to have to try this out - I'm getting a Vox wah on a trade, but volume pedals to me are more useful than wahs. it will be nice to have both in one without actually spending any money or getting stuck with another brand (I like the Vox sound).

    The other mods look interesting too.
     
  9. sanders4617

    sanders4617 Member

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    Thanks. Yeah I need to give it true-bypass as well. Might order the parts soon.
     
  10. EunosFD

    EunosFD Member

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    I may very well have to try this as well. I've been putting off buying another vol. pedal for quite a while now (not quite sure why either). This would certainly be cheap enough to do. Does anybody know if the RI's have changed much over the years? Mine is from the early 90's fwiw.
     
  11. mistercoffee1

    mistercoffee1 Member

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    The 90's v847 are fine. It's the current v847A model that has changed making it more difficult to mod.
     
  12. EunosFD

    EunosFD Member

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    Ok cool beans. I'm looking inside mine right now, but can't quite determine where the cap is from the above diagram. I probably won't do it until I get a switch to put in there anyway.
     
  13. mistercoffee1

    mistercoffee1 Member

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    It's the (black) cap in the lower right hand corner of this pic:
    [​IMG]
    The cap's ground side would be the right leg, when referring to the photo above.
     
  14. EunosFD

    EunosFD Member

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    Ah okay got it now. Was having a hard time visualizing it. :AOK
     
  15. EunosFD

    EunosFD Member

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    Ok, got around to doing this today (actually, make that my dad did it as he's an old school EE & an ace with the soldering iron; I'm far from it so better safe than sorry). It's not perfect, but for literally $0 investment (already had a great switch salvaged from something) it was a no brainer. It doesn't totally zero out the volume when rocked all the way back, but I suspect it's a circuit design issue since it wasn't really meant to be a vol pedal. Works like a charm though and the switch is easy to flip with my foot whilst playing. :AOK
     
  16. 12StringStrat

    12StringStrat Member

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    Yeah, that's what I remember. The rocker of a wah doesn't rock far enough to turn a normal wah pot from end to end. However, certainly a cheap investment in expanding the use of a pedal.
    There's also a very similar thing for a Boss TR-2 tremolo, you change one resistor to fix the volume drop problem and when you turn the level of trem to zero, it acts as a little bit of a boost.

     
  17. Axekisser

    Axekisser Member

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    You could adjust the sweep to turn off completely but then it might not (probably not!) ramp the volume all the way up. I solved that problem by installing a true bypass switch. Works great. In fact, I think a volume pedal should have a true bypass switch so it can be taken out of the circuit. It then acts like a direct line line to the board or amp. I don't recall any VPs that have a TB so you heard it here first! I should market one!!
     
  18. EunosFD

    EunosFD Member

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    Actually I noticed that there's a slight volume boost with the pedal in volume mode when turned full on. It's not a major difference mind you, but it's noticeable. Then again the circuit may impart some sort of tonal characteristic of it's own which gives that impression. I'll probably still end up popping a tb switch in there eventually anyway. We're gonna try our hand at building some fun circuits so I'll just pick up an extra one when the parts order goes in. Funny thing is I was going to just sell the thing as I rarely if ever use it, but looks like it'll be sticking around for a bit longer now. :D
     
  19. Uma Floresta

    Uma Floresta Senior Member

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    I did the mod, and it doesn't turn the volume all the way down - close though. I took off the little white plastic piece that holds the treadle gear in place and tried playing with the potentiometer travel, and it doesn't go all the way to zero volume at any point.

    Still, it's worth doing. There might even be a slight volume boost at the loudest point, which is useful.
     

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