Polarity in Single Coils

[Rodc]

Hi guys,

Another question about pickups, this time it's polarity.

For this Tele kit I ordered the Tonerider TRT 2B Hot Classic (bridge) and a for the neck a Tonerider 'Hot 90' Neck P90. I have the Tonerider 'Hot 90' Neck P90 in a SG copy guitar along with a matching P90 in the bridge. I have a Tele kit with a Tonerider Vintage Plus in the bridge.

I checked the polarity of the vintage plus and the p90 with a magnet and they both have the same polarity. I checked online about reversing the polarity of the P90 by swapping around the magnets. That's the easy part. Swapping the wires around is the hard part then they say it won't be exactly right anyway.

Any ideas guys before I order a matching PU for the TRT 2B? Thanks in advance..

[Simon Barden]

Pickups from the same manufacturer should come with the same overall polarity, whether humbuckers or single coils, so that a two pickup combination wired in parallel or series will be ‘in phase’. Mixing pickups from different manufacturers risks the signal polarities being reversed, so you get a thin ‘out of phase’ sound when two (or more) pickups are selected.

I presume you want to achieve a RWRP pickup so that a two pickup selection is hum cancelling? And both pickups currently have the magnets arranged so the upper pole pieces are both N or both S?

This is when it might be best if you can swap the standard braided single conductor output wire P90s normally come with for a twin conductor shielded cable. The shield connects to ground at one end and the pickup base plate at the other, allowing you to reverse the pickup connections and wire for series/parallel and also incorporate a polarity switch for the mid position.

As far as I can make out, there should be no meaningful difference between the signal produced by just swapping the output wires round with the magnet flipped. If you look at a small section of the coil windings on a pickup that has been wound ‘backwards’ compared to a ‘forward’ wind (based on the length from the ‘hot’ or ‘ground’ output connection) will produce a slightly different signal as physically they will be in different places, but averaged out over the pickup, the result will be the same. The only time there may be a very slight difference I know of would be on a early PAF-style pickups (exact copies) where thicker lead wires were joined to the winding wire, and some of the lead wire was wound around the bobbin, causing some disruption in the first layers of coil windings on one side of the pickup only, adding in a slight asymmetry to the signal if there were ‘forward’ and ‘reverse’ versions of the coil fitted in the same place. Later, the coil wires on humbuckers were joined to the lead wires outside the coil. On Fender single coils, the coil wire was always taken to the lead wire connection pads AFAIK.

Vintage P-90s may also have had a length of lead wire incorporated in the windings, as they came before PAFs and Gibson probably continued the same winding method used on the P-90, but at some point as production volumes increased, I expect they changed to externally connecting the lead wires on all pickups as it was quicker.

I doubt any Tonerider will have thicker lead wires that are wound on the bobbin, so for your pickups, there will be no measurable sonic difference.

[Rodc]

Pickups from the same manufacturer should come with the same overall polarity, whether humbuckers or single coils, so that a two pickup combination wired in parallel or series will be ‘in phase’. Mixing pickups from different manufacturers risks the signal polarities being reversed, so you get a thin ‘out of phase’ sound when two (or more) pickups are selected.

I presume you want to achieve a RWRP pickup so that a two pickup selection is hum cancelling? And both pickups currently have the magnets arranged so the upper pole pieces are both N or both S?

This is when it might be best if you can swap the standard braided single conductor output wire P90s normally come with for a twin conductor shielded cable. The shield connects to ground at one end and the pickup base plate at the other, allowing you to reverse the pickup connections and wire for series/parallel and also incorporate a polarity switch for the mid position.

As far as I can make out, there should be no meaningful difference between the signal produced by just swapping the output wires round with the magnet flipped. If you look at a small section of the coil windings on a pickup that has been wound ‘backwards’ compared to a ‘forward’ wind (based on the length from the ‘hot’ or ‘ground’ output connection) will produce a slightly different signal as physically they will be in different places), but averaged out over the pickup, the result will be the same. The only time there may be a very slight difference I know of would be on a early PAF-style pickups (exact copies) where thicker lead wires were joined to the winding wire, and some of the lead wire was wound around the bobbin, causing some disruption in the first layers of coil windings on one side of the pickup only, adding in a slight asymmetry to the signal if there were ‘forward’ and ‘reverse’ versions of the coil fitted in the same place. Later, the coil wires on humbuckers were joined to the lead wires outside the coil. On Fender single coils, the coil wire was always taken to the lead wire connection pads AFAIK.

Vintage P-90s may also have had a length of lead wire incorporated in the windings, as they came before PAFs and Gibson probably continued the same winding method used on the P-90, but at some point as production volumes increased, I expect they changed to externally connecting the lead wires on all pickups as it was quicker.

I doubt any Tonerider will have thicker lead wires that are wound on the bobbin, so for your pickups, there will be no measurable sonic difference.

Thanks again Simon. You are fountain of knowledge!

Yes, that's correct. It's the hum cancelling is what I'm after when the selector switch is in the middle position.

I just checked again with a magnet in a small bottle, the bridge and neck pickup are the same polarity. That is the bridge in the tele and neck in the SG.
I thought the same as you, same brand pickups would have the same polarity so you could mix pickups on a guitar and keep the noise cancelling. Only possibility is I've put the pick ups in the SG around the wrong way which I highly doubt as I had the the neck pickup first. It was fitted with a old EMG humbucker then swapped it out for the bridge P90 later down the track.

I sent Tonerider a email asking what they thought but haven't heard back from them as yet.

The kit from Pitbull should be here in a few days with the pickups. I'll check them too but don't like my chances of them being the right polarity.

I appreciate your time and advice thanks Simon..

[Rodc]

Kit just arrived Simon. Checked the pickups and they both have the same polarity.

As you mentioned previously, it's hard to get in there to do any modifications. Photo attached.

[Simon Barden]

Yes. Looks like the braid’s been soldered on last, making it difficult to remove the baseplate. You’d have do desolder the lead wires first, which isn’t that easy a job. You might do it with a solder sucker, but desoldering braid might be better. Even so, a big risk of the wires still being connected by solder if you pull them, and those coil wires are easy to snap.

I think the risks outweigh the benefits here. If you mod anything, mod the bridge pickup.

[Rodc]

Yes. Looks like the braid’s been soldered on last, making it difficult to remove the baseplate. You’d have do desolder the lead wires first, which isn’t that easy a job. You might do it with a solder sucker, but desoldering braid might be better. Even so, a big risk of the wires still being connected by solder if you pull them, and those coil wires are easy to snap.

I think the risks outweigh the benefits here. If you mod anything, mod the bridge pickup.

After a think about it I bit the bullet and went for it Simon. I said to myself, this could be a $75 lesson if I stuff it up.

First up I took the screws out of the base plate. That gave me a bit more room to get in with the soldering iron. I un-soldered the braided earth wire from the plate then. I carefully moved the plate done to snip the earth wire from the coil which was just hanging in there. Before I got a chance it snapped off on the underside of the plate.
On a closer look the hole where the solder joined the earth winding around the pickup to the small piece of braided wire that snapped was full of wax. Very, very carefully I used the soldering iron to melt the wax cleaning the tip as I went.
Tinned a bit of wiring heated up the solder mound on the top side of the plate a little and pushed the tinned end of the wire into the solder mound.
Put some shrink wrap on it and then ran the earth wire and the hot wire to opposite holes in the plate so they would lock and not break at the soldered joins.
I made up a earth wire with a round connector and used one of the plate screws to secure it. Swapped the magnets around and somehow after all that it worked!!

Thanks again Simon for the ideas..

[bassdude]

... somehow after all that it worked!!

Nice rescue!

Peter

[Simon Barden]

Nice work. Glad it still makes a sound.

[Rodc]

Thanks Simon and BD, I actually surprised myself!