No volume on E string

[tparker]

I made my own pickup recently and for the most part it sounds great. But, the high E is too quiet despite have a pole piece closest to the string. Here's a litany of odd things about this home made weird pickup. Maybe one of these things caused the problem.

• The pole pieces are threaded magnets to allow them to be set at different heights. FeCrCo magnets comparable to AlNiCo 5
• The pickup is a Jazzmaster style, but the windings start a little out from the poles due to the threading through a plastic bobbin.
• I messed up winding the pickup several times and caught a slack loop inside the windings. Because of the depth of the slack loop I just tucked it in and crossed fingers it wouldn't mess things up too much.
• I had to clean up the threads on the magnets a little  in that the machining was sloppy and they wouldn't thread.
• I had jazz flat wound string on the guitar and the E was a little soft on the store bought pickup. But way soft on my pickup.

[curtisa]

Can you back the polepieces all the way out and swap the high-E pole with a different one? Maybe the magnetic strength of the polepiece under the high-E is particularly weak?

I note that FeCrCo is mentioned as having similar magnetic properties to AlNiCo5, but there are a number of disadvantages that may reduce magnetic performance including:

Quote

• If the final heat treatment is not performed, the magnetic performance is very poor
• Easily demagnetised or remagnetised in a different direction

Source:

https://www.eclipsemagnetics.com/na/magnetic-materials-iron-chrome-cobalt-fecrco/

[tparker]

Yes, I can do that. The guitar is in pieces again, so it will be a while before I get to try that Curtisa. The G or D might be good candidates. 

I'm also wondering if I should pass it through the magnetizer again. But will try swapping first. 

[Bizman62]

Since it's the outermost polepiece in the row, could it be possible that the threading has cut the shielding of the coil wire, grounding the magnet? Then again, wouldn't that affect the entire pickup? Just thinking without any deep knowledge.

[mistermikev]

I'm gonna guess the polarity of the magnet/pole-piece is flipped on the e string (for the win).

[tparker]

Polarity was correct and the pole piece was fully charged. Sorry Mistermikev. The guitar is doing much better, but still not as loud as I would like. Here's what I changed.

I notice the threaded post under the bridge on the high E was a little loose. I've got to do some more work to really fix this, but it is better. Maybe that was part of it?

I had 10.5 strings on the guitar. I swapped the E for an 11. Still not as loud as I would like, but much better.

Just for experimentation I removed the pole from the G string since it is the loudest. To my surprise the volume only dipped a little. What did happen was that the strings definition was lost. 

Wondering if maybe the this is because the Jazzmaster pickups are so wide? Maybe the pole pieces just don't shape the electric field as much narrow pickups. Any thoughts?