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wiring question woes

Discussion in 'Pickups & Electronics [BG]' started by peaveyGrind6Man, Apr 2, 2013.

  1. peaveyGrind6Man


    Apr 1, 2013
    Ive been looking for a diagram I want to Cut out the second volume pot and put in a blend pot but retain a 4 pot set up curently bridge pickup volume, tone
    Neck pickup volume, tone

    reason for this is I love the ability to cut the tone from one or both pick ups. It helps me dig into deeper sounds.

    desired wiring would be master volume pot, Blend pot
    bridge tone pot, neck tone pot.
  2. Stealth did a diagram for that, if you search for it.

    The reason why no one has done it is that it requires the use of fixed resistors to isolate the signal paths. You lose output that way, and especially with the increased load of the blend pot. You might consider leaving the grounds off of the blend to reduce loading.
  3. Cadfael


    Jan 4, 2013
    Germany, EU
    EDIT ...

    HOT from PU to tone pot and from the same connector to be balance (middle).
    From balance to Master volume.

    The tone pots have to be parallel between PU and balance ...
  4. Ok, I just did some searching, and cannot find it. I might have mis-attributed this same diagram to someone a couple of months ago, too.

    If you can't find the diagram somewhere on this forum, I'll draw it up an post it, if you need it.
  5. gumtown


    May 7, 2007
    New Zealand
    There are two ways to wire it, both ways require one of the volume pots to be replaced for the balance pot, either a high value linear (B curve) with each PU into each end and the center to the volume pot, or a dual ganged log volume pot with one PU wired in reverse, so the volume increases one way while the other volume is decreasing, with both centre pins wired together and off to the volume pot.
  6. No, that doesn't work. The wiper terminals of a blend pot cannot be used as outputs. This is because turning away from the center detent will decrease output impedance instead of input impedance on one pickup. If you go to solo a pickup, there will be no output.
  7. gumtown


    May 7, 2007
    New Zealand
    Like this

    or you could use a 3 way selector switch.
  8. Cadfael


    Jan 4, 2013
    Germany, EU
    I attached a pdf with what you want.

    Master Volume > Balance > T/T for the pickups ...

    There are different kinds of balance pots. Most have a small paper how it has to be soldered (where to be GND/HOT).

    Attached Files:

  9. That's not going to work. At least not any better than VVTT Jazz bass wiring works. You need to add resistors to isolate the signal paths, otherwise both tone controls will be masters.
  10. Cadfael


    Jan 4, 2013
    Germany, EU

    Then the balance is turned fully to the "neck", there is 500k resistance between the "theoretically working" capacitor of the bridge PU and the "main HOT". If the bridge capacitor would have influence, the bridge PU would have influence as well because both parallely use the same "exit/entrance" ...

    The "resistors to isolate the signal paths" is the balance pot itself.
    As PU an tone control are parallel, the balance pot is the "barrier for influence".

    I am no electronic but a "skilled metal worker". So I create schematics like making water or oil pipelines. If the "mixing battery" says: "Only cold water", it doesn't matter what you do to the hot water.
    A closed balance pot does the same (adding aresistor in series) to the tone pot as if the tone pot was closed itself ...

    Am I wrong?
    Watch the schematic below ...
  11. When the blend is not soloing pickups, the closer you get to the center detent, the more influence one tone control has over the opposite pickup. You're putting two tone controls parallel to each other, because the pickups are parallel to each other. You need to put a resistance between the pickups so the tone controls won't be parallel to each other.
  12. This is the proper wiring for VBTT.
  13. Cadfael


    Jan 4, 2013
    Germany, EU
    In Germany we have the word "Jein" (Ja + Nein > yes + no).

    I had been a guitar player for 25 years before I converted to the real good ...
    No one cares that Les Paul guitar tone controlls influence the whole sound when the toggle is in the middle position.

    I think the influence is more a theoretical than a practical issue ...
    Then you blend the PUs, the strength of influence also decreases as a resistor is put in in series.

    Wouldn't it work to make a "Strat tone pot wiring"?
    Not two capacitors which might influence eachother, but only on capacitor, wired to GND and on the other end to both tone pot ends?!
    Then the capacitors can't influence each other because there is only one. The amount of influence on the PUs depends on the tone pot settings and on the balance setting ...
  14. This is the reason why this wiring is not desirable. People quickly lost interest in the original stacked-knob Jazz bass wiring, because it made everything too dark. And it's really not practical to want two tone controls either.

    The way Strats work is to have two tone pots and one capacitor, that is switched by the pickup selector switch. The only time you will see both pots in the circuit at the same time is in the neck+middle position. And in that position, the pots are parallel to each other, sharing the one capacitor, so whichever one is at the lower setting will take effect on both pickups.
  15. Cadfael


    Jan 4, 2013
    Germany, EU
    That's 100% right for a Strat - but not for a balance pot bass!
    The capacitor is not "totally parallel" to the Master Volume (like in a Strat with its switch)!
    The blend pot also has influence on the tone pots because they setting of the balance pot "builds a series barrier" (like your "always serial barrier" ...

    Am I wrong???
  16. LUpton

    LUpton Supporting Member

    Oct 22, 2012
    Tampa, FL
    Probably too old for this sh--

    That is a lovely diagram, except for the omitted grounds on the tone caps. If the tone caps are not grounded (by tying all the pots together) the tone controls won't work. (I know this was probably a simple omission in the drawing, but noobs might wire things up and go "***? Tone ctrls don't work?")


  17. What omitted grounds?
    They are wired to the back of the pots, and the pots will be grounded one way or another.
  18. Cadfael


    Jan 4, 2013
    Germany, EU
    Hi line6man,

    most people know "what is meant" by the schematic - noobs might not.
    That's all Larry wanted to say ...
  19. I have drawn hundreds of diagrams in the same fashion, and this is the first time anyone has ever pointed this out.
  20. LUpton

    LUpton Supporting Member

    Oct 22, 2012
    Tampa, FL
    Probably too old for this sh--
    Not trying to start a fight or impugn anyone's knowledge, just trying to achieve a little clarity.


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