Squier CV Mustang bass tone

Discussion in 'Pickups & Electronics [BG]' started by Captainforbes, Mar 14, 2022.

  1. Captainforbes

    Captainforbes

    Mar 14, 2022
    I’ve just bought a used Squier Mustang Bass, looks lovely……
    The tone pot doesn’t seem to do anything …… on removing the plate to see the wiring, the wire from the pickups to the tone pot looks flattened at one spot, as if it’s somehow been squashed. I’m wondering if the wire could be damaged inside the insulation.
    Any ideas how I could test the wire conductivity and tone pot with a multimeter without dismantling???
     
  2. dwizum

    dwizum

    Dec 21, 2018
    I'd say "with a multimeter" but if you had a multimeter I would assume you wouldn't have asked?

    You can test it by deliberately shorting the tone pot end of the wire to ground. Get as creative as you want in how to do that. Could be as simple as a bent paperclip. Or alligator clips and a short length of wire. Any way to create a conductive path between the wire in question and any grounded point on the bass. The grounded point could be the sleeve terminal on the jack, or anywhere on the wiring harness that's grounded.

    Follow the questionable wire to the tone pot, and you'll see that it's soldered to one of the three terminals on the pot. Short that terminal of the pot to ground, and attempt to play some notes on the bass. If you get sound, the wire is indeed broken. If the bass is completely silent, the wire is intact.
     
  3. Captainforbes

    Captainforbes

    Mar 14, 2022
    Thanks for that. Im handy with 12v electrics on a boat, but guitar wiring is new to me.
     
  4. iiipopes

    iiipopes Supporting Member

    May 4, 2009
    It's not that different: hot, ground, extra shunt to the tone control off the side of the volume control, then to ground on the other side of the pots. The way you wire a tach on a 12-volt system is actually very similar to wiring an electric instrument passive pickup. Since you can read wiring diagrams, just pull a schematic for your instrument wiring off google and you can troubleshoot it from there.
     
  5. Captainforbes

    Captainforbes

    Mar 14, 2022
    Thanks for that.
    Has anyone any idea if full size pots will fit in the body cavity? Stock pots are mini sized. Rough measurements look very tight (1 mm clearance each side maybe, and maybe depends how how centered the pot stem holes are in the cover plate.
     
  6. iiipopes

    iiipopes Supporting Member

    May 4, 2009
    Probably not. But Bournes does make mini-pots. I have them on a project Jaguar H (MM pickup, 32-inch scale). Same thing: traditional sized pots wouldn't fit the control cavity. I changed out the stock 500 kohm pots and the .022 guitar capacitor for traditional 250 kohm audio taper pots and a traditional .047 tone cap and the tone went from edgy to big and round with the stock pickup.

    Is your bass a single split pickup bass, or is it the P-J two pickup model? If it is the single split pickup model, it is wired like a vintage 60's style Precision bass; if the P-J model, there are several diagrams that pop up on images when you google.
     
  7. dwizum

    dwizum

    Dec 21, 2018
    Pots fitting in the cavity is half the battle, if you're switching brands or types of pots, make sure you're checking the diameter of the bushings on the shafts as well as the shaft size and style to be sure the pots will fit in the holes on your control plate and your knobs will work on the shafts.
     
  8. Captainforbes

    Captainforbes

    Mar 14, 2022
    I think I will need to drill out the pot shaft holes in the cover plate from metric to imperial... about 1mm I think. The coverplate is stainless steel..... any advice on how to do it? SS is pretty hard!
     

  9. Use a slow speed on the, preferably, drill press and some cutting oil. Clean everything off well when you’re done. Oh, clamp the plate to the drill press table. It can hurt when the bit catches and spins the plate. Not that I know about that… :rolleyes:
     
  10. Captainforbes

    Captainforbes

    Mar 14, 2022
    Ive got no drill press, so I guess we can compare notes on spinning coverplate injuries ........
     
    dwizum likes this.
  11. dwizum

    dwizum

    Dec 21, 2018
    A round file is probably the next best option if you're not equipped or comfortable with drilling metal. If you're doing it with a drill, especially a handheld drill, a step bit is safer and easier to control than a typical twist bit.
     
    Matt Liebenau likes this.
  12. Captainforbes

    Captainforbes

    Mar 14, 2022
    I think a round file might be my first step. Im a retired dentist, so I know a thing or 2 about drilling. But most of my experience is drilling with diamond coated burs at 450,000 RPM!.... water cooled of course. Now that Im retired I have no access to that kind of stuff ...... tho I suppose I could try a Dremel?
     
    Matt Liebenau likes this.

  13. Small world! I install and repair dental equipment. Dremel could work too. Keep us posted on how it works out.