51 split coil P Bass pickup

[Helmholtz]

The problem is the ohms per foot varies, especially back when that pickup was originally wound. You are assuming the ohms per foot is equal on the new spool, and it most likely is not. You would need to figure out the original wires ohms per foot, use the original reading to figure out the approximate number of winds, then apply that many winds of the new wire and the final ohms reading of the new wire will be a little different.

That's why it is always best to wire the reproduction to the same inductance as the original.

[LtKojak]

Variation between different AWG 42 wire can not be very big.

Really? What about 7% for Min-nom and another 7% for Max-nom? 14% in total. Another 4% for Single or Heavy enamel.

Not so big that it is a problem.

That's a matter of prospective, I guess...

I think a winding tension may cause more variation on wires DCR per meter.

You "think" or you "know"?

[okabass]

Ok. I say "same type AWG"
It is always good to be as accurate as possible, but do you think the original -say- 7ender pickup is originally made so accurate. What I've learned they were not.

It is always important to I think the order of magnitude. Variation between different AWG 42 wire can not be very big. Not so big that it is a problem. For example I think a winding tension may cause more variation on wires DCR per meter.

[Jim Shine]

Don't quite follow. If I have a broken Strat PU, and I know the DCR. Say it is (or was) 5,6 kΩ/ AWG 42. Then what I'm doing wrong if I wind it to 5,6 kΩ with same type AWG 42?

I can measure PU's inductance, capacitance, magnetic flux density (tesla/gauss), DCR . I have for example an oscilloscope, function generator and this .https://www.amazon.com/Labs-DE-5000-.../dp/B005EMT8PC

The problem is the ohms per foot varies, especially back when that pickup was originally wound. You are assuming the ohms per foot is equal on the new spool, and it most likely is not. You would need to figure out the original wires ohms per foot, use the original reading to figure out the approximate number of winds, then apply that many winds of the new wire and the final ohms reading of the new wire will be a little different.

[okabass]

PS.
I compared a split coil, a stack coil and original type single coil on my '51 reissue P bass. To my taste (rock, blues, soul...) the Stack ( S.Duncan clone) was the best, then Single coil and Split coil. What I looked is 1) character (a bit more lo end is good). 2) noisless.
Split coil type sees to be kind of lame (cancellation?). Single is ok. with most situations. Stack is noisless, and gives very good bass sound. Like a good original single coil, but more good lo end and output.

[okabass]

Agreed, but if I see MM, I usually don't bother, and move on!
After all you are the one seeking help, and most here talk in inches, but feel free to do what you like.
I was just making a suggestion!
GL with your pickup.
T

Thanks. One half winded to 4,36 kΩ / 11800 turns.
https://www.dropbox.com/s/3pwpa87xk9...12010.jpg?dl=0
8,72 kΩ may be too hot, but we'll see. (or listen)

[big_teee]

Yes, mags total length is 20 mm . Mag diameter is 5 mm. I prefer to use SI units, metric, cause that is what has agreed many decades ago (for ex. USA 1866, but not much in use). Well I think it is polite to accept the units the writer uses. I do inch to mm conversation all the time. Luckily there are many easy to use web calculators.
https://www.rapidtables.com/convert/...nch-to-mm.html

Agreed, but if I see MM, I usually don't bother, and move on!
After all you are the one seeking help, and most here talk in inches, but feel free to do what you like.
I was just making a suggestion!
GL with your pickup.
T

[okabass]

When you specify 20mm you are talking overall length?
When talking magnet height, you only count the magnet height between the flats.
That height area is what you are talking about concerning brightness.
I too agree 1/2 inch is enough between the flats.
I also never hear you say what the magnet diameter is.
Most of us prefer using inches, instead of MM, due to all the old published data, and the use of bobbin calculating software.
So when using data for pickup bobbin cores, use length, width, height between the flats, & flange diameter.
AC readings are great, but lots of basic hobby winders, use turns, and DCR, because of tools they have available.

T
** Hopefully this can be a place for all degree of pickup builders, regardless of the expertise, & technical tools they have available!

Yes, mags total length is 20 mm . Mag diameter is 5 mm.
I prefer to use SI units, metric, cause that is what has agreed many decades ago (for ex. USA 1866, but not too much in use). Well I think it is polite to accept the units the writer uses. If you care only turns and DCR, you can easily ignore the other measurements.
I do inch to mm conversation all the time. Luckily there are many easy to use web calculators.
https://www.rapidtables.com/convert/...nch-to-mm.html

[big_teee]

Ok. Thanks. 10 % higher f res may be enough. I made it with 20 mm mags cause I already have those.


I mean the whole PU. If I remember it right the magnets were 1/2" long. The flatworks are a few mm. Coils height is then ca. 10mm.

When you specify 20mm you are talking overall length?
When talking magnet height, you only count the magnet height between the flats.
That height area is what you are talking about concerning brightness.
I too agree 1/2 inch is enough between the flats.
I also never hear you say what the magnet diameter is.
Most of us prefer using inches, instead of MM, due to all the old published data, and the use of bobbin calculating software.
So when using data for pickup bobbin cores, use length, width, height between the flats, & flange diameter.
AC readings are great, but lots of basic hobby winders, use turns, and DCR, because of tools they have available.

T
** Hopefully this can be a place for all degree of pickup builders, regardless of the expertise, & technical tools they have available!

[okabass]

Everything else being equal, yes. But the difference will not be dramatic. You might get a reduction of inductance by 10% to 20%, meaning a resonant frequency higher by 5% to 10%. But alternatively you could reduce your turns count on the wider and shorter coil for the same treble increase and still get more output, because this coil places the turns closer to the strings.

Ok. Thanks. 10 % higher f res may be enough. I made it with 20 mm mags cause I already have those.

Actually 13mm is very close to 1/2 inch (12,7mm).

I mean the whole PU. If I remember it right the magnets were 1/2" long. The flatworks are a few mm. Coil's height is then ca. 10 mm.

[Helmholtz]

If I wind the same turns count on a wider and shorter coil or thinner and longer coil, the latter has less inductance, which leads I get more treble?

Everything else being equal, yes. But the difference will not be dramatic. You might get a reduction of inductance by 10% to 20%, meaning a resonant frequency higher by 5% to 10%. But alternatively you could reduce your turns count on the wider and shorter coil for the same treble increase and still get more output, because this coil places the turns closer to the strings.

Yes 13 mm isn't much more, but it might be enough. Can't find now the original '51 PU height, but I think it is total 1/2 ". So I think 13 mm is some 3 mm more.

Actually 13mm is very close to 1/2 inch (12,7mm).

[okabass]

That's what I'm asking:do you accept to rewind a p'up when all you've got is a DC reading?

Because unless is a relatively known design, so I can refer to my fellow winder's factual knowledge of the said p'up, I wouldn't even expect to be nowhere near, let alone "nail it", tone-wise, just by matching a DC reading.

Don't quite follow. If I have a broken Strat PU, and I know the DCR. Say it is (or was) 5,6 kΩ/ AWG 42. Then what I'm doing wrong if I wind it to 5,6 kΩ with same type AWG 42?

I can measure PU's inductance, capacitance, magnetic flux density (tesla/gauss), DCR . I have for example an oscilloscope, function generator and this .https://www.amazon.com/Labs-DE-5000-.../dp/B005EMT8PC

[okabass]

There is no physical justification for such claim. And if listening comparisons seem to confirm it, I suspect that the wider and shorter coil had higher inductance. Whenever evaluating the sonic influence of a change in dimensions or other parameter it is essential to wire/select the samples to be compared for identical inductivity.
Otherwise chances are that you are primarily hearing the effect of the different inductances.

If the differently shaped coils to be compared have the same number of turns and the same cores/magnets/wire size, the thinner and longer coil will have less inductance, somewhat higher capacitance and most of all less output with respect to the shorter and wider coil.

Your coil height of 13mm doesn't seem to be extraordinary, so the effects won't be too strong depending on what other size you are comparing to.

HI
Ok. Thanks. If you say so.
If I wind the same turns count on a wider and shorter coil or thinner and longer coil, the latter has less inductance, which leads I get more treble?
Yes 13 mm isn't much more, but it might be enough. Can't find now the original '51 PU height, but I think it is total 1/2 ". So I think 13 mm is some 3 mm more.

[Helmholtz]

The DCR is just a measure of the total length of wire in a coil for a given/known wire gauge. The direct effect of the DCR on frequency response (i.e. resonance Q) is rather weak. The dominant factors for frequency response are inductance and (cable) capacitance as well as the resistance values of the instrument's control pots.

[LtKojak]

If I rewind a PU which DCR is documented 7 kΩ

That's what I'm asking:do you accept to rewind a p'up when all you've got is a DC reading?

Because unless is a relatively known design, so I can refer to my fellow winder's factual knowledge of the said p'up, I wouldn't even expect to be nowhere near, let alone "nail it", tone-wise, just by matching a DC reading.