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series/parallel question

Discussion in 'Pickups & Electronics [BG]' started by MichaelScott, Aug 2, 2004.


  1. MichaelScott

    MichaelScott

    Jul 27, 2004
    Moorpark CA
    Hey guys (and gals),

    I am pretty new to this forum (and playing bass). I have a basic question that wasn’t in the FAQ at the top of the page.

    What does it mean to run your pups in series or parallel? How do they differentiate in sound/volume/tone?

    Thanks!
     
  2. ZuluFunk

    ZuluFunk

    Apr 14, 2001
    Pennsylvania
    I don't know the answer...but I know Ken Smith does.
    My old BT-4 has a parallel/serial switch. I'm not sure which is which, but if I have the p'up blend knob at 50-50 the tone is really thin - until I flip that switch. Then it's like going from sugar water to molasses.

    I think it has something about running in phase vs out of phase where the fields either enhance or diminish the overall signal.

    I recently dropped a pre into an Acacia w/ passive Lane Poors with independent volume pots. One of the reasons I did this was that with both p'ups at full I actually lost volume. Now it has one volume and a blend. I don't have the same problem.

    Call Ken Smith's shop, you can find the the number at www.kensmithbasses.com
     
  3. RyanHelms

    RyanHelms

    Sep 20, 2003
    Cleveland, OH
    Someone else please jump in if any of this is incorrect or confusing, but...

    Here's a detailed technical explanation concerning series/parallel - it applies to any pickups.
    http://www.guitarnuts.com/wiring/serpar.php

    "ZuluFunk - I think it has something about running in phase vs out of phase where the fields either enhance or diminish the overall signal."

    Phase is another ball 'o wax from series/parallel ;) but you're right about it's implications. read all about it here -
    http://www.guitarnuts.com/wiring/phase.php

    (the Guitar Nuts write-ups are assuming Strat pickup configurations, but the theory applies in general)

    Series/parallel is about path (point A to point B), phase is about polarity. Combining the two, you can have series in phase or series out of phase, likewise for parallel.

    Here's a quick diagram assuming two single coils, minus pots or switches, just to clearly illustrate the difference.
    [​IMG]

    As for sound, volume, tone? Typically, seperate single coils are wired in parallel. Individual coils within humbuckers are in series with each other, then the humbuckers as a whole are in parallel with each other. Series is a touch "hotter" with perhaps some more mid. The results vary though, with regard to pickups themselves.

    Hope I got all that right...
    -Ryan
     
  4. David Wilson

    David Wilson Administrator Staff Member Administrator Supporting Member

    Oct 14, 2002
    Lower Westchester, NY
    A standard Jazz bass with two single coil pickups and V/V/T controls is operating in parallel. In series operation you essentially combine the two single coils into a single humbucker by joining the neck ground wire to the bridge hot wire. This can be hardwired or wired with a push/pull pot for switchable operation.

    Tonally, for series there'll generally be a thicker midrange and less high end and slightly less bass. Parallel will have more bass and high end, but less midrange.


    In terms of implementing it on a bass, series/parallel can be done in different ways.

    You can take two individual pickups and run them in series/parallel - this is the most common mod discussed here. Also, you can do series/parallel operations on individual pickups that support this - such as Dimarzio Model J and Ultrajazz pickups. The Fender Roscoe Beck 5 bass lets you choose series/parallel/single coil operation for both the neck and bridge pickups.
     
  5. David Wilson

    David Wilson Administrator Staff Member Administrator Supporting Member

    Oct 14, 2002
    Lower Westchester, NY
    Ryan,
    nice job, I was looking for a diagram to illustrate it.
     
  6. RyanHelms

    RyanHelms

    Sep 20, 2003
    Cleveland, OH
    Thanks, David.

    It's too fun to resist drawing diagrams for any and everything...especially with access to server space :D
     
  7. Juneau

    Juneau

    Jul 15, 2004
    Dallas, TX.
    I tell ya on my Dingwall, Series is way louder than parallel hehe.
     
  8. MichaelScott

    MichaelScott

    Jul 27, 2004
    Moorpark CA
    Thank you for the replys all. It was exactly what I wanted to know.
     
  9. mgmadian

    mgmadian

    Feb 4, 2002
    Austin, TX
    Great summary... just to offer my .02's worth of relevant experience here, I've got DiMarzio UltraJazz's in my early 70's Jazz, wired so that I can select either both pups together in series or both together in parallel (each one individually is wired in series).

    In this bass, running both together in series yields more bottom end than running both together in parallel. The rest is as David mentioned, i.e. series has less high-end and more pronounced mid-emphasis (and different mids, too... more of a honk than in parallel). Personally, I like running them both in series for fingerstyle, and both in parallel for slap.
     
  10. David Wilson

    David Wilson Administrator Staff Member Administrator Supporting Member

    Oct 14, 2002
    Lower Westchester, NY
    So, the pickups are hard wired in series themselves but you have a master series/parallel mod? That's the standard s/p mod. Or do you mean you can individually put each pickup in series/parallel?
    How do you find it works in practice live, with the different volume levels between series/parallel?
     
  11. mgmadian

    mgmadian

    Feb 4, 2002
    Austin, TX
    Each pickup is hard-wired (individually) in series, and a 4-position rotary pickup selector knob enables me to select between Neck, Both (Series), Both (Parallel), and Bridge pup. A good guitar tech did this for me, so unfortunately I can't be of much help in describing exactly how it's wired, but I understand that Sheldon Dingwall now offers a rotary knob designed for this purpose (and which comes with wiring instructions).

    Very true, there's a volume jump when both are in series vs. other positions... but it doesn't bother me much, mainly because I'm aware of it, and I tend to hit rather hard when thumping, which makes up for it somewhat.

    One more thing, the bass also has an all-pots bypass capability whereby pulling up the volume knob bypasses the volume and passive tone... tends to be most useful when in the Both (Series) position.
     
  12. KSB - Ken Smith

    KSB - Ken Smith Banned Commercial User

    Mar 1, 2002
    Perkasie, PA USA
    Owner: Ken Smith Basses, Ltd.
    Zulu, Your Bass must have the old Phase (in/out) switch. For S/P, we would put 2 of them in, one for each pickup. Parallel is our standard wiring (switch down) and with the Series Switch (up) it sounds Deeper and fatter with a slight loss of Treble.