Two humbucker guitar quieter when both pickups are on

[Ptron]

This is a two humbucker, two volume, single tone guitar. It's noticably quieter when both pickups are on than with either individually.

I flipped one of the pickups around for a quick check to see if it was backwards and out of phase. It didn't seem to make a difference.

It's wired correctly as far as I can tell but that's not very far.

I think at least one of the pickups is a replacement as they're different. The unconnected white wire from the bridge pickup looks to be the center tap as it measures ~4.5k to ground whole the red is ~9k. It's a Hamer explorer (same one from the long bushing pickup selector thread) Everything sounds about right as far as I can tell, it's just quieter with the pickup selector in the middle position. Any ideas?

[David Schwab]

How did you "flip the pickup" around? If you just turned it 180° in it's mounting ring, that wont change the phase.

You want to reverse the hot and ground of the pickup, but make sure the pickup has a separate conductor from the shield. It it's just the braided coax and the center conductor, that wont work.

Does the yellow wire have more than the white and red and shield? If it has another insulated wire (do I see black?), then swap the red and black.

If it doesn't, then you either need to rewire the pickup, or flip one of the magnets around.

And make sure you tape up that white wire!

[Ptron]

Thanks for the reply, David.

How did you "flip the pickup" around? If you just turned it 180° in it's mounting ring, that wont change the phase.

Oh yeah, I guess it wouldn't. (where's the emberassed smiley) That's what I did.

You want to reverse the hot and ground of the pickup, but make sure the pickup has a separate conductor from the shield. It it's just the braided coax and the center conductor, that wont work.

I'm not sure they do have a separate negative lead. Both pickup's hardware read ground with a meter but perhaps they're getting that connection through something else. The sheild paint perhaps? I'll have to look into that when I'm home. The neck pickup just has the two wires and the braided sheild which I assumed was directly connected to the ground wire, either internally or back at the pickup. It could be floating and getting it's ground from whatever's grounding the pickup hardware. Again, I'll have to check on that.

Does the yellow wire have more than the white and red and shield? If it has another insulated wire (do I see black?), then swap the red and black.

If it doesn't, then you either need to rewire the pickup, or flip one of the magnets around.

That black wire is bare stranded wire, covered in heatshrink, and heavier guage than the red or white wires, so I assume it's the sheild. I could peel back the heatshrink and make sure it's not two wires stripped and twisted together. Flipping a magnet around sounds a little scary, I toasted a pickup once by breaking the winding where it came off the bobbin, but I'll keep that in mind.

And make sure you tape up that white wire!

It's got some heatshrink on it but I'll tape it back to yellow jacket for extras.

[Ronsonic]

It is normal, standard, typical that a two pickup guitar be a little quieter with both pickups on and both volumes turned all the way up.

Try this. Plug in, turn the volumes and tone full up; listen to the bridge pup for volume, now the neck. THen go to both, it's quieter. Now roll one of the volumes back just a little and listen to it get louder before it gets quieter. They are all like that. All of 'em.

Why I don't know. I just fix this stuff.

[Ptron]

It is normal, standard, typical that a two pickup guitar be a little quieter with both pickups on and both volumes turned all the way up.

Try this. Plug in, turn the volumes and tone full up; listen to the bridge pup for volume, now the neck. THen go to both, it's quieter. Now roll one of the volumes back just a little and listen to it get louder before it gets quieter. They are all like that. All of 'em.

Why I don't know. I just fix this stuff.

I never knew that. And I have several two pickup guitars.

I guess I never noticed because with all the ones I own (this guitar isn't mine) one pickup is dominantly louder than the other. That pickup dominates the tone and volume when in the middle position. It's really annoying actually. It's like that on my Tele, my Gretsch, my DeArmond,....

[Steve Conner]

Surely that's what the pickup height adjustment screws are for. If one pickup is louder than the other, move it further away from the strings and move the quieter one closer.

[Mark Hammer]

Even though the pickups may be electronically in phase, such that there should not be any electronic cancellation of identical signals sensed, that doesn't mean the string is in identical phase (i.e., presenting identical signals) above both pickups.

[Ptron]

after further review...

Sorry to dig up this old thread. I kind of forgot about this whole thing. I started playing around with this guitar again and comparing it to my other two pickup guitars. I think the pickups are out of phase.

1) The middle position significantly quieter. If the middle position is quieter in my other guitars, it's subtle at best
2) Middle position sound thin. It sounds pretty flat on my other guitars.
3) Rolling off either volume causes it to get louder, all the way to zero. It gets quieter on my other guitars. If there is a volume peak, it's subtle.
4) There is a more sweeping-notch, almost wah-like tone change as one or the other Volumes is rolled off, with a “sweet spot” in the rotation where the effect is most drasctic tone and volume-wise.

So I take it there is, or at least was, no industry standard for the polarity of pickups? I guess most modern pickups probably have a separate sheild so they are reversible.

Couple other interesting things I noticed while playing around:
On most of the guitars -
- When adjusting pickup height, the bridge pickup needed to be closer to the strings to sound as loud as the neck pickup.
- Even with the pickup adjusted to sound equally loud seperately (to my abused ears at least) the neck pickup dominates in the middle position, i.e rolling off the bridge volume makes a much subtler difference than rolling off neck volume.
- The exception to all these is my tele but I think teles have notoriously weak neck pickups.

[Rick Turner]

You're hearing the effect of one pickup "loading" the other. That's how it is with passively combining pickups in parallel. The simple explanation is that each pickup "sees" the other as a path to ground with a resistance equal to the DCR of the load pickup. It gets trickier than that, but one way to hear the effect is to put a resistor of a value equal to one of the pickup values from hot to ground with one pickup selected. Then try that with the other pickup. You'll hear a similar (though not exactly the same) change in volume. There is the issue of parallel inductance and capacitance to deal with, too, but basically each pickup acts as a volume and tone control on its mate.

[Krwkka]

You're hearing the effect of one pickup "loading" the other. That's how it is with passively combining pickups in parallel. The simple explanation is that each pickup "sees" the other as a path to ground with a resistance equal to the DCR of the load pickup. It gets trickier than that, but one way to hear the effect is to put a resistor of a value equal to one of the pickup values from hot to ground with one pickup selected. Then try that with the other pickup. You'll hear a similar (though not exactly the same) change in volume. There is the issue of parallel inductance and capacitance to deal with, too, but basically each pickup acts as a volume and tone control on its mate.

That is a lovely answer. I just ran across this question and this answers it perfectly.

(Yes, it's an old thread and most of the posters are deceased—but I'm still here and grateful!)