Um, wire gauge and number of coils (total amount of wire) determine DC resistance. The thickness of the wire insulation and to a lesser extent the manner of winding contributes to intra-coil capacitance, which also affects inductance, resonant frequency, and frequency and slope of high-end rolloff. Shape and size of the coil contribute to impedance, as a function of inductance compared to resistance.
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Will 1K make a difference?
- Thread starter Pbman
- Start date
Which is what you should count. It’s a lot easier and accurate to count turns than try to match exact DCR.
Yes, because the actual length of wire around the bobbin varies, so the total amount of wire, in spite of having the same number of turns, will also vary, which causes the variance in DC resistance.
It may be easier to count turns, but remember that all turns are not created equal.
Changing the winding pattern will change the overall turn length. Iow, decreasing the number of turns to wind from bottom to top will take fewer turns, but those turns will be longer than the turns which were wound picture perfect (like a compressed coil spring).
Different tension while winding will also affect the total length of wire for a given amount of turns.
And, temperature will affect the DCR readings. Higher temps will show a higher DCR. So, the DCR isn't the "be all, end all" for accurate measurements, but as long as everything is around room temperature it should be close enough for government work.
When pickup makers talk about pickups they talk about number of turns and AWG. When testing pickup windings it's a lot, lot easier to make pickups with different numbers of turns than DCR. I find it difficult to measure DCR when winding. I don't care about the DCR at all, I wind for turns. 10 000 turns is 10 000 turns in J pickup as well as in a single coil in Wal pickup.
Wire has an ohms/length value depending on the metal and wire gauge.. All that matters is the total length of wire used for DCR. The thermal coefficient is insignificant in the temp range of human comfort so won't make any difference. If the wires get stretched during the winding process the resistance will be a little higher but not likely to be a significant factor. Magnets have no effect on DCR.
Temperature does make a difference. If you don't believe me measure the DCR on one in the morning when it's going to be about 100 degrees that day. Write down your DCR reading, and put the pickup in sealed container (like a black mailbox) and measure it again after it's set in the sun for several hours.The DCR reading will be higher.
Just magnet strength. Alnico II doesn't have a tone that is different to Alnico V. The only interesting factor is the strength. Magnets don't impart tone.
We will have to disagree on that. With guitar pickups, just changing the magnet can make a very noticeable difference in tone.
And again, it's the number of
Please tell me how do you wind for accurate DCR? When I go to pickup makers forum DCR is very rare info, they talk about turns. When selling pickups they talk about DCR because that's how buyers determine pickups, higher DCR> higher output>less highs. You can make a pickup sound the same with different DCR by changing the wire gauge and keeping the number of turns the same.
I agree that temperature does affect resistance. My point was generally when we're talking about temperatures that are comfortable for people, it won't make much difference. Looking online, copper wire has a change of +0.39% per degree C. You would need a 46 degree F difference to account for the approximately 10% difference the OP was seeing in the pickups. Maybe he took one outside in the cold to take the DCR measurement, and measured the other in front of a toasty fire? That could account for the difference!
Sure, because different magnets have different strengths and may also have slight differences in the shape of the field they throw. But the chemical makeup is incidental and truly not relevant. The strength is the key. So the statement 'magnets don't impart tone' may be misconstrued. In a sense they really don't because they simply supply a magnetic field. The field and the coil and strings do the work. The coil is much more important but, the pickup won't work without all elements in place. It's maybe just semantics.
Alnico vs ceramic/neodymium has some difference in the way they effect on eddy currents and treble response especially if the magnets are inside the coil. If magnets are outside the coil and pickup design have steel poles or blade magnet type has less effect. Strength of course has an effect to the electronic properties of the pickup.
Interestingly Bill Lawrence had the same opinion as me, but what did he know.
You need to do more research. You can either be right or wrong; this isn't something you have an opinion on.
Swapping out mags with the same dimensions, but of different types, will change the tone as the magnetic strength changes. That is it. Alnico V doesn't have more 'bark' or any of that crap.
Once I bought an Epiphone P-90 on ebay. It spent a few hours in a solar heated mailbox on a 100+ degree afternoon. I took it inside and measured the DCR, over 12k (I don't remember the exact number). A few hours later after being in the AC it measured a little less than 10k. That's over 2k. I was shocked. Maybe the metal cover had something to do with it.
I brought it up because different temperatures, just as different turn lengths on coils with the same amount of turns, will give different DCR readings. Iow, x number of feet of wire won't always have the same DCR if the temperature changes enough; and x number of turns of wire won't always have the same DCR because the total length of wire can vary.
Going by turn count is the easiest and most practical way to wind coils, but there's room for inconsistencies.
Lots of variables, it seems. Bass resonance, wire thickness, number of windings, magnet type, magnet strength.....
I am a simple country boy from Idaho who does not understand such technical variables. Here is my simple view: The PV '63 p'up is the best I have ever heard. Fat, but with noteworthy sparkle at the mids and highs. I also have an '04 Am Std P with the '62 AVRI p'up which is a completely different animal, which also sounds great. If the '62 p'up sounds like a Labrador barking, the '63 sounds like a Mastif.
According to my understanding, 'overwound' p'ups have fatter bottom ends. This is consistent with my limited experience. This is how the PV '63 and Geezer p'ups sound. Then again, you guys have forgotten more technical information than I have ever known. My $.02.
I am a simple country boy from Idaho who does not understand such technical variables. Here is my simple view: The PV '63 p'up is the best I have ever heard. Fat, but with noteworthy sparkle at the mids and highs. I also have an '04 Am Std P with the '62 AVRI p'up which is a completely different animal, which also sounds great. If the '62 p'up sounds like a Labrador barking, the '63 sounds like a Mastif.
According to my understanding, 'overwound' p'ups have fatter bottom ends. This is consistent with my limited experience. This is how the PV '63 and Geezer p'ups sound. Then again, you guys have forgotten more technical information than I have ever known. My $.02.
