Weird Wiring Issue...

TelePaul

TelePaul

J to the R O C
Hi lads, having a bit of a weird issue with some wiring. I've been messing about with various pickup combinations. I've installed everything in a HSS configuartion correctly in that they all work and are nice and phase coherrent. However, when using both the neck and middle together, there's no instance of hum-cancelling. In fact, I noticed a slight hump in the overall noise floor when compared to other positions.This strikes me as odd because it sounds perfectly in phase, and I'm worried that flipping the neck will cause me problems.

Any thoughts?
 
TelePaul said:
Hi lads, having a bit of a weird issue with some wiring. I've been messing about with various pickup combinations. I've installed everything in a HSS configuartion correctly in that they all work and are nice and phase coherrent. However, when using both the neck and middle together, there's no instance of hum-cancelling. In fact, I noticed a slight hump in the overall noise floor when compared to other positions.This strikes me as odd because it sounds perfectly in phase, and I'm worried that flipping the neck will cause me problems.

Any thoughts?
Click to expand...
Yes. It's not the wiring; your pickups are alike. In order to have hum canceling with two single coil pickups, one of them needs to be RWRP (reverse wound and reverse polarity). The reverse winding makes the hum cancel when they are both on, but the reverse (magnetic) polarity makes the RWRP pickup reversed TWICE, which puts it back in phase with the other one for picking up signal from the strings. You need to get a RWRP pickup. It doesn't matter which position you put it in.
 
Sorry boys, as soon as I posted I knew I'd left soemthing out! The middle pickup is RW/RP which is why I'm so confused. I've been chopping and changing though and am using a Gibson Humbucker, Texas Special in the middle and generic Texas Special knock-off in the neck.
 
TelePaul said:
Sorry boys, as soon as I posted I knew I'd left soemthing out! The middle pickup is RW/RP which is why I'm so confused. I've been chopping and changing though and am using a Gibson Humbucker, Texas Special in the middle and generic Texas Special knock-off in the neck.
Click to expand...
Well then, it appears that both your single coil pickups may be RWRP.
 
TelePaul said:
Wow, interesting observation! I might swap out the neck for the stock and see if it goes away
Click to expand...
I think you can tell by placing the pickups face to face. If they repel, they have the same magnetic polarity, and if they attract, not.
 
How I do it, and this just works for me, is a two step process. First, I take a compass to the pickup. It's either 'North' or 'South'. Then I hook up the pickup to my old analog VOM. Set it for R x 1K and you might get a reading of '6' for a single coil or '8' for a typical PAF. Now take a small flat blade screwdriver, and gently tap any pole piece on that pickup. The reading will either deflect 'upwards' or 'downwards'.
Pickups that are both 'North' and deflect 'upwards' (as one example) will be in phase. You can also look at how the leads come off of the bobbin on a Strat-type pickup. Facing you, it should be the 'hot' or white colored lead on the left and the 'ground' or black colored lead on the right. If the black lead is on the left, that's likely a reverse wind. And if it's a reverse polarity, you should get a hum cancelling effect when used with a 'regular' pickup.
This isn't 100% written in stone, but the typical pickups I buy follow this. Keep in mind some manufacturers seem to get a sick thrill out of being @ssholes and not following convention. I know mixing Seymour Duncan and DiMarzio Strat pickups never works. Sometimes you gotta wire one pickup with 'white' as 'ground' just to make them get along.
If you can check all that, you'll save time taking strings off and removing the pick guard just to muck with the wiring when you have phasing issues after soldering all morning.
 
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