foolish newbie questions...

Discussion in 'Pickups & Electronics [BG]' started by cloren, Dec 7, 2007.

  1. cloren


    Nov 15, 2007
    san francisco
    I've researched everything from tone woods to electronics in search of how to achieve a quality instrument with a "good sound" and thusly put in hours of set-up and repair on my basses. I do have a couple unanswered questions though :

    1) I've read on many sites and seen wiring diagrams for a jazz bass setup w/ 250k audio volume, 250k blend, and 250k tone pot; however, I'm awaiting a 500k blend - I know the rule of thumb is 250k=warmth and 500k=brights but how does this rule apply when dealing with a blend pot? In other words, what tonal difference is there b/w a 250k and a 500k blend?

    2) in reference to star grounding- I bought a copper terminal lug under the assumption that it'll act as a grounding 'star'. Will this work or is there something more appropriate and if so where do I find it? There was nothing on and googling it yielded nothing helpful. (the terminal lug is too big to fit into the grounding hole in my MIM j bass - I may have to drill to find a place for it.... I don't know why, but I have a bad feeling about this)
  2. DavidRavenMoon

    DavidRavenMoon Inactive

    Oct 20, 2004
    "Good sound" is a matter of personal opinion. ;) You've already lost me thinking a Jazz is a "good sound".

    If you already have a 250K volume and tone control, you don't need two more 250K resistors going to ground. They all add up. 500K should be fine.

    250K doesn't add warmth, it just takes away highs, which then makes the lows more prominent.

    You find nothing about star grounding at StewMac (or Seymour Duncan, or DiMarzio, etc.) because it's not needed in guitar or bass wiring. It's become some kind of urban myth perpetrated by sites like Guitar Nutz.

    Assuming you have your bass shielded, and the pots are sitting on foil, you have already undone any star grounding.

    It's something that's done in things like Tube amps where there's high voltages involved. You aren't going to get a ground loop in a passive bass when none of the common returns have a much higher potential than the main instrument ground.

    But, sure, you can connect all your grounds to one point, assuming you can make all your wire reach. If it makes things harder than need be, don't bother.

    People have been soldering ground connections to the backs of pots for many years, because it's convenient and it provides a proper grounding point, since all those parts are connected to the main instrument ground. But the ground connection is the one on your output jack, and ground is made at the amplifier. There is no actual ground in the bass.

    Just follow the schematics you see on places like StewMac. Good soldering and keeping your wires neat and no longer than needed are what's important.

    And what is the "grounding hole" on your bass? There is no grounding hole. You will see a ground wire running to the bridge, to ground the strings, and you might also see a wire with a lug screwed into the wood to ground the conductive paint, if that was used.
  3. cloren


    Nov 15, 2007
    san francisco
    hey thanks for clearing up those things for me I really appreciate it. I ought to get a book on this electronic stuff- I'm totally lost in some of the terminology.