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Front Coil/Parallel HB/Rear Coil wiring

jesterbass

jesterbass

Apr 20, 2007
366
131
#1
Hello people, I have a set of Nordstrand Dual Coil pickups, with four conductors. They are currently wired with one 3-way (on-on-on) switch each, for Series HB/Single/Parallel HB mode. Is it possible to wire the switches for Front Coil/Parallel HB/Rear Coil instead? That's the preferred order but it really does not matter. Any links/pointers/schematics would be very appreciated.

Thanks!
 
#2
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#4
Hey line6man, I just got a little free time to try and fiddle with my humbuckers' coil tapping. Trying the schematic at bottom right (North/Parallel/South) makes the single coil modes work ok, but the parallel humbucking gives me very very low volume as if there's some sort of cancellation. Shouldn't it be one + pole and one - pole on the switch so that parallel works? My switch is type 1.
 
#5
jesterbass said:
Hey line6man, I just got a little free time to try and fiddle with my humbuckers' coil tapping. Trying the schematic at bottom right (North/Parallel/South) makes the single coil modes work ok, but the parallel humbucking gives me very very low volume as if there's some sort of cancellation. Shouldn't it be one + pole and one - pole on the switch so that parallel works? My switch is type 1.
Click to expand...

If the single coil modes sound fine, but the parallel mode is weak, perhaps the coils are out of phase.
Try swapping the NC+ and NC- leads.
 
#6
Hmmm... I just did that and it works! But, that poses another problem. :) I was hoping I could set up both neck and bridge pickups for north/parallel/south thus having 4 combinations of hum cancelling single coil modes (north/north, north/south, south/north, south/south). But if NC- and SC+ are on the switch, 2 of these will be humcancelling and 2 with probably double the noise. Are two 3-way switches enough to set something like this up? It seems I am pushing the envelope here. :)

(Btw, an observation of mine is that there is quite a significant change of tone when changing from north to south.)

PS. (about the possibility of 4 hum cancelling single coil modes, your initial schematic made it seem possible, the only thing that needed to be done is to wire NC+, SC+ on the first switch and NC-, SC- on the second switch. This way at all times the neck coil will cancel the bridge coil. But of course as I witnessed the parallel mode does not work)
 
#7
I did a little more searching and it seems that after all, with two 3-way switches and maintaining parallel mode on each pickup, 2 out of 4 single coil combinations will be hum cancelling because of the polarities. line6man, do you know/can think of a practical way (i.e. not having a dozen switches on your bass) to have parallel switching with 4 hum cancelling single coil modes? I wonder if there is a method to analyze this requirement and come up with some sort of circuit, the simplest that can achieve it.
 
#8
the coils themselves will determine whether they hum-cancel or not. either they have opposite magnetic polarity from each other or they don't, and thus either can be wired to cancel or can't, and no amount of switching will change that.

you can have one coil from one pickup cancel with one coil from the other, and you can have the other coil from the first pickup cancel with the other coil from the second, but that's it.

(use a small magnet to determine which coils are opposite each other; if one coil attracts the magnet, the coil that repels it will be the coil you can wire to hum-cancel.)
 
#9
I see, I get what you 're saying. A first (wrong) thought is that by switching the leads you can in a sense "reverse" the polarity, but you would need to revese the coil's orientation towards the strings. Thanks for the input, that solves the "dilemma" about which modes to select as hum cancelling. I 'll wire that up tomorra and let you guys know how it goes. :)
 
#10
you can change the coil wire's polarity with wiring, but you can't change the magnet's. they both have to be reversed to get hum-canceling.
 
#11
Well, everything worked out nicely. :) The bass/pickups make an interesting combination, and there's quite a few tones available. I might record some comparison clips of various coil settings. Thanks again people.
 

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