Will this dual coil setup work?

Discussion in 'Pickups & Electronics [BG]' started by Landyachtz, Nov 14, 2005.

  1. Landyachtz


    Sep 5, 2005
    Tempe, AZ
    Ok, I've searched for this, and it seems no one else has done this, so either it can't be done, or no one has tried. For my new 5 string I'm using Nordstrand Dual Coils. What I'd like to do is have a switch for each pickup that switches

    [Parallel HB - Top Coil(SC) - Bottom Coil(SC) - Series HB]

    Also I was thinking of adding a master Par/series switch for the 2 pickups (series bypasses blend)

    1) Is this feasible?

    2) I know for each pickup I'd essentially need a DP4T switch, and I have yet to find something like this. Does anyone make one?

    3)In SC modes, as long as I left the blend dead center would get a hum? (I know little about coil polarity, but I'm thinking this might kill this whole idea of having multiple SC options)

    I understand there will be volume differences between the settings, my main idea with this was to have a main live setting, but for the bass to be an incredibly versatile studio bass capable of a multitude of sounds. I sincerely appreciate any help with this :)
  2. mahrous


    Aug 13, 2005
    just email or PM Carey Nordstrand himself.

    he has also posted how he did this for a customer last month during October.
  3. Landyachtz


    Sep 5, 2005
    Tempe, AZ
    I saw the post Carey made, however he explained how to install a switch to do [Parallel - Series - SC]. What I'm wondering is....

    Can I somehow (with either a DP4T toggle, or rotary) make the individual pickups switchable from [Parallel - Series - bottom coil cut - top coil cut]

    I think I will just e-mail Carey, but I'm thinking this won't work because of the coil polarity.
  4. Moo

    Moo Banned

    Dec 14, 2002
    Oakland, CA
    With Barts at least, you can use either the 2 outermost or 2 innermost coils of the 4 coils of 2 pickups and they'll be humbucking with the blend in the middle. This should work with any matched humbuckers. If one is hotter than the other you may get a tiny bit of hum in center position SC's.
  5. elros


    Apr 24, 2004
    Proprietor, Helland Musikk Teknologi
    With individual coil switches per humbucking pickup, some of the SC settings will not be humbucking. Let's see if I can explain it.

    In each pickup there are two coils, let's call them + and - since they are wound opposite ways. Now, if you combine the + and the - they'll be humbucking together. this also works for the + of one pickup and the - of the other. If you however use both + coils, or both - coils, you won't get humbucking. Also if you've got one pickup in humbucking mode and the other in SC mode, you won't get total humbucking although one pickup is hum free.
    Clear as mud?

    In my bass I also have two dual coil pickups, and I've wired them so that there are three positions: position 1 activates the outmost coils of each pickup, position 2 activates all coils, and position 3 activates the inner coils of each pickup. All three positions are humbucking ( 1 and 3 only if both volume pots are on full, of course). See more details and schematic on my web page here.

    hope that helps?
  6. Landyachtz


    Sep 5, 2005
    Tempe, AZ
    ok, assuming I understand you correctly. If my pickups are laid out like this:

    l_______________________________________l Neck

    l_______________________________________l Bridge

    God I hope that came out right. So if they are like this and I have the 'S' coil from the neck pickup, and the 'S' coil from the bridge pickup active, I would get a bad hum? If that's correct, than this is what I thought might kill this idea (coil polarity that is).

    So what if I used a DP3T for each pickup [Par HB - Ser HB - Single coil] then somehow insert a third switch that, when either or both of the pickups are in SC mode, changes from inside to outside coils. So using my diagram I could have the bridge pickup in series HB mode, and the neck pickup could be in Single coil mode. This third switch would allow me to change from the N to S coil on the neck pickup (in this scenario). But, when both pickups are in SC mode, it switches inside to outside (essentially it would always be doing this, but the HB modes would not have the third switch in their path).

    After all this I'd like to put another switch that changes how the pickups are wired together, this would go after the other switches, but before the blend/volume. So this would be a master series/parallel switch, with the series mode bypassing the blend control. I know this is very complicated, but I think if I can pull it off I will have one very versatile bass. Does any of that make sense?
  7. DavidRavenMoon

    DavidRavenMoon Banned

    Oct 20, 2004
    It's actually the polarity of the magnet that cancels the hum, so you need one pickup with a north and one with a south.

    As odd as it seems, the coil doesn't actually sense the strings, but senses the disturbance in the magnet's field, which is caused by the strings (although the strings often become magnetized themselves from being close to the magnets and then the coil will directly pick them up.. you can actually remove the magnet...).

    The coils do have to be wound opposite also, but just reversing the polarity of the coil and not the magnet will give you an out of phase signal.

    I'm not sure how useful selecting just the bottom coil would be either.
  8. It does and it's doable. You need a couple of DP3T, one for each Series/Parallel/SC, then one DPDT for inner/outer and then a 3PDT for the overall Series/Parallel with blend bypass.

    For the DP3Ts you can use either a rotary switch (that's what I use in my J/MM for S/P/SC of the MM pu) like this one, which is actually a 4P3T: http://www.newark.com/NewarkWebCommerce/newark/en_US/endecaSearch/partDetail.jsp?SKU=81F1014&N=0 (ignore where it says 4PST, the number of positions is actually adjustable between 1 and 12 with an index ring) or you could use the blade type switches used in Telecasters: http://www.guitarelectronics.com/product/SWL31. As for a 3PDT, here's one: http://www.newark.com/NewarkWebCommerce/newark/en_US/endecaSearch/partDetail.jsp?SKU=21F663&N=0

    I can draft a schematic for you or, if you have problems going from schematic to wiring, give me the wire colour codes of the pu's and I'll do a wiring diagram instead.
  9. I just thougth of an alternative you may find more convenient to use plus it uses more "normal" switches: instead of two Series/Parallel/SC and one Inner/Outer, you could have two [Series or SC]/Parallel (these would be DPDTs, so you could even use push/pulls on the V and T controls) and one Inner/Series/Outer (a DP3T on/off/on, like these: http://www.guitarelectronics.com/product/SWM22 or http://www.guitarelectronics.com/product/SWMB22 ). The overall Series/Parallel wouldn't change (3PDT). Your call!

    EDIT: The usual case of typing faster than you think :meh: of course this option allows for fewer combinations, since you can't have one pickup in series and the other one in SC. Oh well...
  10. Ok, here's the schematic (to make it clearer I've circled the option selected on each switch, so the way it's shown it would be "inner coil of neck pu in series with bridge pu wired in parallel"):