5 String Jazz Bass Pickup Issue

[TheGrateOz]

Hello,

I have wound a set of 5 string jazz pickups (stacked coils similar to the SD stacks). I have my pots setup with a 250k volume on each pickup and a 250k master tone. I also have a .047uF Orange Drop Cap on the tone pot.

The pickups measure 13k Neck and 15k Bridge. They sound great individually, but when I have one full volume and bring the other to full volume, the volume drops on the last couple degrees of twist on the pot.

Here's a link to how I wired them: Wiring Diagram

Any idea why that would be? Thanks for your help.

-Oz

[David Schwab]

They are out of phase with each other. Swap the hot and ground on one of them.

Let me guess, are the magnets opposite polarity between the two pickups? For stacked pickups they should both be the same.

And why use an orange drop cap? Just use a cap. It doesn't matter which kind.

[David King]

You will occasionally experience a tiny bit of volume drop with both pickups on full due to the slight differences in phase from different locations of the PU along the string's length. The further apart the pickups are -the more noticeable the effect.

[David Schwab]

That's true, you get a little volume drop. The two pickups load each other, and there's always some phase cancelation.

If it's a drastic drop, and the low end gets very thin, then they are out of phase. You sometimes notice it more when you have the neck pickup backed off a little, because it's sometimes louder than the bridge. So both full on sounds not so thin.

[TheGrateOz]

Thanks Guys,

I will check all of those things. Appreciate the detailed commentary.