Convert dual volume PJ bass to no-pot

Discussion in 'Pickups & Electronics [BG]' started by H3R3T1K, Sep 2, 2017.

  1. I have a passive PJ with a VV (no tone) configuration. I never mess with the pots. Now my understanding is that wiring the pups straight to the jack would change the tone of the bass making it sound brighter. I hear a lot of top artists have their pots hard soldered in position 10 (all the way up). Have you guys experience with that? No more checking the knobs. Just stomp the tuner to mute. Sounds great to me.
    Last edited: Sep 2, 2017
  2. Nev375


    Nov 2, 2010
    Yeah, you can do that if you want.

    I wouldn't want to because I don't use a tuner pedal and I kinda like having a volume knob. Not only for turning the bass off, but i find it useful to do volume swells with my pinky rather than a foot pedal.
  3. If you don't want the change in tone, just solder a resistor across the output jack. If you had 500k pots, then use a 220k resistor. If you had 250k pots, then use a 100k resistor.
    superheavyfunk likes this.
  4. Cadfael


    Jan 4, 2013
    Germany, EU
    It is always try-and-error ...

    But you can try it with a 100k, 150k or 220k resistor, soldered parallel to the jack (HOT and GND).
    In position "10" the pot is "just a parallel resistor". So, the pot can be replaced by a normal resistor.

    You can also try a (linear) 250k trim pot and find out which position is best.
    Left or right to HOT and middle to GND.

    EDIT: line6man was faster!

    EDIT2: On a PJ the pots are parallel.
    Serieal resistors > R1 + R2 = Rtotal
    Parallel resistors > 1/R1 + 1/R2 = 1/Rtotal
    So, 1/250 + 1/250 = 2/250 = 1/125
    That's why we recommend 100-220k resistors ...
    superheavyfunk likes this.
  5. Am I correct assuming that you always use both pups on full? If not You could try adding at least some kind of pick up selector. No resistence of pots but still different sounds with the flick of a switch.
  6. Cadfael


    Jan 4, 2013
    Germany, EU
    The selector doean't effect the resonance frequency of the PU - but this is essintial for the sound.
    The higher the pot resistance, the higher is the resonance frequency.
    That's why most SCs have 250 resistors while most HBs have 500k. HBs need "more high ferquencies", added by the higher pot value.

    With a spimple selector, the resonance frequency remains the same.

    If you use a selector:
    1x 220k parralel to PU A,
    1x 220k parralel to PU B,
    Both connected to the selector.

    If one PU is on 220k (like a pot), both on > 110k parallel (like two pots) ...
  7. It's a minor detail, but there is a difference between adding more of something, and subtracting less of it. Pots cannot add anything into the circuit, but you can preserve more of the original signal by "subtracting" less from it.
    Cadfael likes this.
  8. Cadfael


    Jan 4, 2013
    Germany, EU
    110% agree!!!!!!!!!!!!!!!!!!!!!!!!!!
    Sorry for the "wrong words"!

    And adding to your post ...
    Bass sounds as we know and ARE USED TO LIKE them are influenced by the pots and "bad speaker systems" ...

    Our mothers liked Elvis, The Beatles, Jimi Hendrix, Kajygogoo, Take That +++
    NO guitar player with distorition would every play directly into a PA. We love the warm, harmonic "tube distortion" by the "bad selsective speaker systems (12" without tweeters). AND we have been used to this sound for about 50 years.

    Bass sounds have changed through the decades. John Entwisle was one of the first popular Roundwound strings players. Level 42 and others made bright sounding basses popular. But who doesn't like the sound of Paul McCartney, playing "Taxman"?!

    A bass PU without resistors (by volume pot or others) is "very special".
    If you want to keep your bass sound "traditional" without any pot, use resistors (like line6man and I wrote).

    Hope you understand what I try to express (sorry - no native speaker).

    But line6man is (like always) right, that passive systems NEVER add anything. They only cut ...
  9. Primary

    Primary TB Assistant

    Here are some related products that TB members are talking about. Clicking on a product will take you to TB’s partner, Primary, where you can find links to TB discussions about these products.

    Jun 21, 2021

Share This Page