Wire tension experiment

[MrCandy]

The following experiment is about the influence of tension to AFC of pickup coils.
The first coil was wound with with extremely high tension on the verge of wire break.
The second was wound with normal tension.
Both coils were wounded 100TPL.

Experiment data:

Max tension spectrogram:


Normal tension spectrogram:


Results:


Please make your own conclusions by comparing the data.

[Mike Sulzer]

Please make your own conclusions by comparing the data.

If I understand correctly, the normal tension has both higher inductance the higher resonant frequency. This means that it has lower capacitance. But the differences caused by small changes in coil capacitance are swamped out by the much larger cable capacitance. This leaves only a small change in resistance to explain any differences. I think the differences in sound are quite small.

[JGundry]

I would love to see a test like this with a big fat bobbin like a P-90.

[copperheadroads]

No surprise here

[MrCandy]

I would love to see a test like this with a big fat bobbin like a P-90.

It wont change meaning and results of the experiment in principle.
Stretching the wire to make its caliber thiner is getting lower Q-factor, that makes sound darker.
Although It is possible that this effect gives almost imperceptible difference in the sound when you use P90.

[MrCandy]

No surprise here

And what did you want to see here? 3 RP in 1 coil?

[MrCandy]

If I understand correctly, the normal tension has both higher inductance the higher resonant frequency. This means that it has lower capacitance. But the differences caused by small changes in coil capacitance are swamped out by the much larger cable capacitance. This leaves only a small change in resistance to explain any differences. I think the differences in sound are quite small.

Yes Mike, all what you said is correct. The difference is very small.
From experience I can say that if Q-factor is different more than 0,1 then the difference is audible, but with great difficulty.
It starts to be audible clear from 0,2 - 0,3 and it is nearly impossible to make such a difference in Q-factor by stretching the wire.

Here is the picture for you to compare Q factors in this experiment:



The thing that really changes the sound is TPL. It is nearly the same 42AWG 5000NT bobbin here but with 83TPL.
You can compare.

[JGundry]

With a large coil like a P90 with 10,000 or so turns a small difference in tension will make a fairly large difference in coil size and density. The larger coil created by lower tension will progressively put more wire on the coil due to the larger relative diameter. After 10,000 or even 5000 turns this difference in the amount of copper on the coil adds up. Also whether a P90 or PAF, if the coil is to be unpotted, the density of the coil windings does IMHO have an affect on the mechanical resonance of the pickup assembly which does have a tonal affect via microphonics. For me the wire tension has more implications beyond any possible change in wire diameter.

Do you have specific numbers in grams as to what you considered normal and high tension for this test?

[copperheadroads]

Nothing ...but tighter dont mean brighter

[MrCandy]

With a large coil like a P90 with 10,000 or so turns a small difference in tension will make a fairly large difference in coil size and density. The larger coil created by lower tension will progressively put more wire on the coil due to the larger relative diameter. After 10,000 or even 5000 turns this difference in the amount of copper on the coil adds up. Also whether a P90 or PAF, if the coil is to be unpotted, the density of the coil windings does IMHO have an affect on the mechanical resonance of the pickup assembly which does have a tonal affect via microphonics. For me the wire tension has more implications beyond any possible change in wire diameter.

Do you have specific numbers in grams as to what you considered normal and high tension for this test?

If you look TAB №1 here, the you will see real TPL influence and wire diameter influence on the coil AFC.
And here you can see 5000 NT 42AWG PE coil and compare its frequency characteristics with same tension coil from TAB 1. All of these coil were unwaxed.
For clarity we recorded knocking microphonic of pickup(two coils) wounded with equivalent/normal tension and the same NT, wire gauge and slugs.You can hear tone difference.
I seriously doubt that you can make such a difference using only tension techniques.

Here this the sample for you:
Knock.mp3
Sound sample of this pickup you can find here.

Also you asked about tension in this experiment.
Normal - 34g
Max - 77g

[JGundry]

If you look TAB №1 here, the you will see real TPL influence and wire diameter influence on the coil AFC.
And here you can see 5000 NT 42AWG PE coil and compare its frequency characteristics with same tension coil from TAB 1. All of these coil were unwaxed.
For clarity we recorded knocking microphonic of pickup(two coils) wounded with equivalent/normal tension and the same NT, wire gauge and slugs.You can hear tone difference.
I seriously doubt that you can make such a difference using only tension techniques.

Here this the sample for you:
[ATTACH]15344[/ATTACH]
Sound sample of this pickup you can find here.

Also you asked about tension in this experiment.
Normal - 34g
Max - 77g

Wow. 77 grams seems extremely high, my tension meter only goes up to 50 grams. I know 34 grams or so is the recommended tension for 42 awg but for a long coil like a P.A.F. bobbin I consider even 34 grams near the top end of the tension I want to wind at.

[MrCandy]

Wow. 77 grams seems extremely high, my tension meter only goes up to 50 grams. I know 34 grams or so is the recommended tension for 42 awg but for a long coil like a P.A.F. bobbin I consider even 34 grams near the top end of the tension I want to wind at.

To make tension 77 grams we removed standard spring from the tensioner and changed it to that which is tougher.
Two additional turns of stopper suport starting from 77g, that was about 85 gram lead to the wire break(but not immediately).
To low dynamic jerking and provide tension stability we used winding speed only 200 turns per minute.

About normal 34g tension. We dont specially made this tension. We came to this numeric value by experiments.
This is the best tension to make winding accurate and dense enough, also this method gives high identity of coils characteristics.