Does Z-coil pole height change sustain? Adjustment method?

Sun May 08, 2022 11:43 am

I'm getting familiar with my Tribute Comanche and I noticed something that I am trying to figure out.

To me, it sounded like my G string was ringing louder and longer than any other string. If I let a chord linger, eventually the G string was all I heard. It seemed to be like this on all 3 pickups.

I thought I would reduce the pole height on G, but found the poles were all bottomed out from the factory setup. So, I raised all the other poles a little instead. This seemed to help, but I didn't go very far, and I only messed with the neck pickup.

Pole height must be adjustable for a reason, does this sound like a reasonable procedure? (I sure like having individually adjustable poles!)

I'd appreciate any thoughts on how to tackle string balancing.

I found this guidance on overall pickup height:
viewtopic.php?f=13&t=3372

Any other setup ideas?

Apologies for the dumb question, I have a lot to learn!

Re: Does Z-coil pole height change sustain? Adjustment metho

Mon May 09, 2022 4:29 am

Not a dumb question at all. I have had similar thoughts and took similar action on my Tribute Bluesboy. Seemed to help a bit but I will await the discussion from more experienced folks.
Thanks for asking.

Re: Does Z-coil pole height change sustain? Adjustment metho

Mon May 09, 2022 6:57 am

I took a closer look at my pickups and they all seem to be screwed in all the way, so they are far from the factory recommendation in that link. I guess what I will do is set them all to factory, see how it sounds, and go from there.

My next related question is, if the factory setting is 1/16" to 3/32" ... how do you set the values in between? Do you just ramp up evenly from one to the other? Or is is more appropriate to do 3/32" for thick strings E-A-D and 1/16" for thin strings G-B-E? Or something else?

I am sure they don't have to be adjusted to the micrometer, but there's probably a best practice!

Re: Does Z-coil pole height change sustain? Adjustment metho

Mon May 09, 2022 12:27 pm

These are good questions! Here's how I approach it:

In general, on electric guitar pickups, the G and the B string sound louder than others (perhaps related to unwound vs. wound, string core diameter vs. wrap, the core's magnetism, etc.). So, I often set those pole pieces as low as possible. Then, I raise the others pole pieces as needed by volume. I play scales to hear the volume of each string relative to its neighbors. Most times, the D string's pole piece needs to be raised the most, and the A string's raised some, but not as much.

I think it's better to use your ear rather than your eye to set pole piece height. (When setting string heights off the fretboard, that's where I measure each one, and gradate the height across the strings.)

But before you adjust individual pole pieces, set the pickup height per factory spec (3/32 and 2/32), as you noted. Then, adjust the individual pole pieces.

[*] Once you have set individual pole pieces, you could also lower the overall pickup height. On Z-coils in particular, this will give a more "vintage" sound (because you are reducing the output to be closer to older less powerful pickups). The inverse square rule applies (easier to think of in terms of raising pickup height): when raising pickups, halving the distance will double the output. Of course, it applies in reverse when lowering pickup heights.
[*] Another benefit of MFD pole piece adjustment: you can stagger them to raise the mids or scoop the mids. So, set them all at the same height, then raise the G and D to increase the mids, or have the G and D lower to scoop the mids.

Re: Does Z-coil pole height change sustain? Adjustment metho

Mon May 09, 2022 12:35 pm

That's great info, thanks! I had no idea that what I heard was actually common.

To adjust the overall height of the Z-coils, the adjustment must be the screws on the pickguard, right? There's nothing else to change unless we're meant to do something with the pickguard off, which would seem strange.

I think my Comanche will sound VERY different once I get the pickups into the factory spec. There is a LOT of room over the poles when they are lowered all the way, as they are now.

Re: Does Z-coil pole height change sustain? Adjustment metho

Mon May 09, 2022 12:40 pm

Yes, the pickguard screws are how you adjust the overall pickup height.

I forgot to address sustain. I think pickup height will affect sustain in that, if the pickups were too close to the strings, the (excess) magnetic pull would cause "drag" on the strings, and then you get poor tone, dead tone, less sustain. So, it's about finding that sweet range to give you clear, ringing, full tone—or whatever tone that you prefer.

Re: Does Z-coil pole height change sustain? Adjustment metho

Mon May 09, 2022 12:46 pm

That all makes sense, thanks again. I actually just read a short article about sustain so I have an idea on what to watch out for.

Re: Does Z-coil pole height change sustain? Adjustment metho

Mon May 09, 2022 3:25 pm

For fun I decided to make a set of 6 feeler gauges to help set string height over the pickup poles. The thickness of the foot just tapers from 3/32" to 2/32".

The laser cutter doesn't have perfect accuracy, but it's close enough for something like this. This will be easier than bending down to look at a ruler and I imagine at least as accurate. Ears are the final measurement anyway, right?

Image

Re: Does Z-coil pole height change sustain? Adjustment metho

Tue May 10, 2022 10:53 am

I used my feeler gauges and dialed in a factory string height setup. I'm glad I took the time to make them, it made the job really easy, no bending over to peek at a ruler. (And I'll never look at another pickup the same way, why don't they all have individually tunable poles?! This is great!)

As you said @tomanche, G and B were somewhat louder by deafault. I found the other strings to be about the same volume/sustain. So, I just dialed down G & B, and I think the guitar sounds pretty OK now. Thinking back I can see the out-of-the-box config was not awesome, the G was truly obnoxious.

When I was doing the adjustments, I realized there are two ways to get to the same string height. If the pickup body is lower, the pole height can be higher to compensate.

Image

I set up my bridge with low body, higher poles and the middle pickup with a higher body and lower poles. To me, they don't appear to behave differently in terms of volume or sustain, but maybe my differences are not extreme enough.

Is the top of the pole all that matters when setting string height over a pickup, or do we expect to hear differences depending on how close the body is, too? I would think that having the body higher and the poles lower would result in a stronger field at the string, but maybe it doesn't make a difference.

Re: Does Z-coil pole height change sustain? Adjustment metho

Tue May 10, 2022 4:19 pm

Horseflesh wrote:Is the top of the pole all that matters when setting string height over a pickup, or do we expect to hear differences depending on how close the body is, too? I would think that having the body higher and the poles lower would result in a stronger field at the string, but maybe it doesn't make a difference.


I think there will be differences depending on the height of the pickup body to the string. This was something that I believe Leo Fender spent a great amount of time researching and experimenting with: all the effects of magnetic field strength, windings, magnet composition (Alnico varieties, ceramic...), magnet charge.... (Not to mention the body wood's grain orientation [!], the bridge footing....)

That's impressive tooling work you did!