Too Bright - Am I not using enough tension?

[big_teee]

Coil doesn't look very full for 5650.
Counter is suspect.
How do you derive 75tpl when you are winding by hand.
I wind by hand, and I have no idea how many tpl?
A 57 or 57+ uses PE wire not poly, and it is usually thicker wire than poly.
So you are comparing apples to oranges.
Try filling the coil up, and do more experimenting.
Try one with the start lead out the bottom, and a full coil.
6000+ turns.
Bridge pickups usually sound better more over wound IMO.
T
** what is the 20 ft lead for in testing, not sure what that is.

[littlewyan]

Is it the counter or am I just winding too tight? I can try winding slower and loosening my grip. I guess if I’m winding tight the wire will be closer together and as a result there will be less wire overall. So the capacitance could look similar to if I wound looser, where there would be more gaps in the wire and more of it.

To determine TPL I just watch the counter and do a bit of quick maths. You’re just watching it go up 75, 150, 225, 300 etc. I might not be winding as fast as you guys either, so it’s easier for me to see.

As for the cable, Helmholtz wanted to know what length I use for testing.

I’ll try lower tension and see what happens.

[mozz]

I don't think lower tension is your problem. I think you need higher tension. Get the coils you have now and try to pinch the wire with your fingers, they should be pretty tight. Being that you are hand guiding, you are no way going to influence the capacitance, it's going to be so random as it is. Actually, trying to duplicate a gibson style pickup, they were never hand guided. Try to act like a machine and go back and forth slowly and be as consistent as you can.

[littlewyan]

So tonight as a test I wound a coil with loose tension, slower speed, 5600 turns and it looks much more full than others I've made. Looks more normal in comparison to others I've seen images of too. It's not quite as neat as I would have liked but the measurements right now are 4.15K, 1.56H 1Khz 1.759Q, 1.17H 100Hz 0.176Q, 71pF 100Khz. I'll measure resistance again in the morning as that should come down a bit, I measured it straight after handling it.

I think my tension is too much, going by my numbers and comparing with other pickups. The pickup in this video has only 5000 turns and looks as full as mine with 5600 turns! https://www.youtube.com/watch?v=8ZH1B9l6IZA&t=

I'll try and get this pickup finished up to compare. Then depending on how it sounds I can try winding one with even more tension, although to be honest I think in my previous attempts I've been on the limit with the amount of tension.

[littlewyan]

Although I did read in another thread on here that for gauging tension someone recommended attaching a AA battery to the end of 12" of coil wire and squeezing the wire inbetween your fingers until the wire stopped slipping. Has anyone tried this? I gave it a go and had to grip pretty tight!

[Helmholtz]

Winding tension and looks of coils shouldn't make much difference with same number of turns.
Lower inductance means more treble.

For reference the values of a Seymour Duncan 59 slug coil (with slugs inserted):
Ls = 1.89H, Q = 2.29, both measured at 1kHz.. DCR = 4.4k.
Low Q would indicate a problem.

[littlewyan]

Is that a neck or bridge coil? Here’s mine with the slugs inserted: Slug bobbin 5604 turns 4.15K 20.5 Degrees C, 2H 1Khz 2.59Q, 2.17H 100Hz 0.32Q, 80pF 100Khz.

[Helmholtz]

SD 59B model.

Your values look good, i.e. no indication of shorted turns.

For a darker sound you need to increase turns number for higher L.

[bbsailor]

Is that a neck or bridge coil? Here’s mine with the slugs inserted: Slug bobbin 5604 turns 4.15K 20.5 Degrees C, 2H 1Khz 2.59Q, 2.17H 100Hz 0.32Q, 80pF 100Khz.

littlewyan,

Hemholtz is correct! Science tells us what effect the coil winding variables have on the output Inductance, Resistance, Turn to turn capacitance, Output level, Resonant frequency and Resonance Q factor. These variables include:
1. AWG wire gauge.
2. Wire insulation dielectric and thickness.
3. Winding method, tight machine wound or scatter winding.
4. Waxing the coil to fill air space to prevent feedback.
5. Output level with turns closer to the vibrating string producing more output than the turns farther away.
6. Coil shape.

Only our ears tell us what sounds good. Then we use science to decode the physical characteristics of the good sounding pickup so it can be replicated by moving the above listed pickup variables in the desired target direction to replicate the desired pickup sound.

Try to understand in which sound direction each variable moves the sound. Increased capacitance reduces higher frequencies. This comes from coil insulation dielectric and thickness. Lower dielectric means less coil turn to turn capacitance. Coil insulation thickness with thicker insulation holding the conductive wire turns farther apart.This means that the bobbin space will allow less space for wire, thus less turns, lower inductance and lower output.

The variables interact. This means that you may need to make tighter windings with less air space between turns to make up for either using a thicker wire or a wire with thicker insulation on the same bobbin wire space. After all of the above, the typical guitar coax adds about 25pf to 30pf of capacitance per foot of cable.

In the end, your ears are the final measuring tool! But having good resistance, capacitance and inductance measurement tools are required to allow you to duplicate pickups that sound good.

Joseph J. Rogowski

[Helmholtz]

PU self-capacitance (e.g. 150pF) acts in parallel with the cable capacitance (often around 500p) and amp input capacitance (typically 150pF).
All these capacitances add and together with PU inductance determine the resonant frequency and HF cutoff.

Different winding tension or TPL may change PU self-capacitance by 50pF.
50pF difference in relation to a total capacitance of maybe 800pF is insignificant.

[littlewyan]

Well I finished building this latest pickup and tested it out. In terms of output it's spot on, it's bright but not harsh or spiky like the last pickup. Kind of reminds me of a T-Top style tone. What if at this point I try a higher TPL? If I increase the number of turns I'll increase the output and I don't really want to make it any hotter.

Total coil stats: 5.2H 1Khz 2.4Q, 5.65H 100Hz 0.41Q, 124pF 100Khz, Alnico 2 Long Smooth magnet.

[littlewyan]

Sorry, I didn't refresh the page before responding so I didn't see the last two replies! I am finding the capacitance measurement quite useless. I've now realised I can vary it a lot just by moving my meter leads! You're both right though about experimenting, I just need to try different winds. I did try different TPL levels before but I don't think I had the tension down. Now I have a baseline of what tight tension I can experiment from here. For instance, I did try a higher TPL before but I think I may have accidentially adjusted tension at the same time. Making the test rather useless.

[Helmholtz]

Do you always adjust for the same PU pole to string distance?
Closer distance increases treble (and volume).

[littlewyan]

Yeah I set them up the same way each time.

[John_H]

Good thread. What are the dimensions of your bobbins? They look tall in the photos.