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Push/pull Pot?

Discussion in 'Pickups & Electronics [BG]' started by verstft, Aug 15, 2016.


  1. verstft

    verstft

    May 16, 2016
    Re-wired my project PJ bass a while back. My current setup is a standard VVT with 250k pots and a 0.47 cap for tone. I'm toying with the idea of having a push/pull pot so I can remove the J pickup entirely from the wiring and have a straight up P setup at the push/pull of a knob.

    I know I've seen Line6Man's wiring diagrams on the forum for a PJ bass with a 3-way switch but I've never seen a push/pull pot setup. Is this type of wiring achievable?

    Cheers,

    Vers
     
  2. lz4005

    lz4005

    Oct 22, 2013
    Sure. It would just be a mute on the J pickup. It would go between the pickup and the volume pot.
     
  3. verstft

    verstft

    May 16, 2016
    Thanks for the reply. I guess I'm trying to remove the J volume potentiometer as well, not just the pickup since that would be adding resistance. I Basically want to switch between VVT with both pickups in the circuit and VT with just the P pickup and no secondary volume pot (exactly how a P bass would be wired) in the circuit. Sorry if this is a stupid question.
     
  4. You should have looked through my whole collection of diagrams. Here is the diagram that you want:
    3778490280_1be45d17ec_o.
     
    Killed_by_Death and verstft like this.
  5. verstft

    verstft

    May 16, 2016
    Thanks I'm going to give this a try! The switch is SPDT right?
     
  6. No, it's DPDT.
     
  7. Charley Umbria

    Charley Umbria I'm Really a Drummer Supporting Member

    Jan 28, 2011
    Rock City, TN
    I did this on my 1980's ESP 400 Series P/J, but used push-pull knobs on both the J-pickup volume and the tone. Pulling up on the J volume knob completely removes the pickup from the circuit, leaving only the P-pickup, volume pot, and tone pot in-line. My wiring layout is slightly different from line6man's, but it accomplishes the same thing. I think his design is actually little cleaner. There's a very small difference in tone between removing the J-pup and just turning it down all the way, but it is there. In truth, however, you'd never notice it, unless the instrument was soloed and you A/B'ed the two sounds. I really just did the mod for fun, and to satisfy my own curiosity.

    The push-pull on the tone knob switches between .047uF and .1uF capacitors for modern and "vintage" P-Bass tones. Standard (down) position is the .047 cap, which I prefer most of the time. However, the bass is strung with GHS Pressurewounds, so using the .1uF cap really gives it a nice, dark "old school" sound.


    i-KVrK8wt-L.
     
  8. verstft

    verstft

    May 16, 2016
    That's awesome. I think part of this project for me is very similar. It's a project bass and I'm loving the experimentation. I need to do some homework on wiring switches though. I like your choice of strings too, seems like you could get an incredible range from thumpy flat to brighter more modern tones, especially with the cap value mod. Seems very versatile.

    Thanks for sharing!
     
  9. iiipopes

    iiipopes

    May 4, 2009
    You can use the SPDT. I must respectfully disagree with Line6Man's drawing. It is too complicated. A simple switch between the hot lead of the pickup and its volume control will do the job, since everything is grounded in the traditional passive style. The only other item I would do is put a 1 meg resistor paralleled with a .1 cap across the switch so that it minimizes the "pop" when switching back and forth.
     
  10. I agree that you can simplify to a SPDT scheme, if desired. It will work the same way.

    Note that you don't want to put the switch between the pickup and volume pot. The switch should go between the volume pot, and the output jack. When the bridge pickup is turned off, you want the load of its pot removed from the circuit.
     
  11. Hopkins

    Hopkins Supporting Member Commercial User

    Nov 17, 2010
    Houston Tx
    Owner/Builder @Hopkins Guitars
    The SPDT vs DPDT argument is a moot point since most push/pull pots have a DPDT switch attached.
     
  12. verstft

    verstft

    May 16, 2016
    Sorry to dig this old thread back up. I ended up going with VVT with a push/pull on the tone to swap between to different caps.

    Got my first experience with wiring a switch and I think I'm ready to tackle the push/pull on the bridge volume to take out of the circuit when pulled.

    I don't quite understand line6Man's diagram. What is it actually doing and how is it taking out the pot from the circuit?