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OK, possibly a stupid question

9/19/2002 9:23 PM
SK	OK, possibly a stupid question Ok, not really a stupid question, I just feel stupid asking it.... What do you use to "match" pickups if they are wound with different guage wire? Do you use the number of turns or the dc resistance, and how do they compare for you? Before I had a counter and a lcr meter I got in the habit of using resistance as that's all I could reliably measure. I came up with a conversion factor of 1.4 (e.g. 6k/42 x1.4= aprox 7.75k/43 and (43dcr x1.4=) aprox 10.8/44) Always seemed to work fairly well(still does, never though to change my "habit") but maybe I'm a bit off or I should be counting turns or something...(all else being equal)seems turns might be more accurate...

9/19/2002 9:23 PM

OK, possibly a stupid question

Ok, not really a stupid question, I just feel stupid asking it....

What do you use to "match" pickups if they are wound with different guage wire? Do you use the number of turns or the dc resistance, and how do they compare for you? Before I had a counter and a lcr meter I got in the habit of using resistance as that's all I could reliably measure. I came up with a conversion factor of 1.4 (e.g. 6k/42 x1.4= aprox 7.75k/43 and (43dcr x1.4=) aprox 10.8/44) Always seemed to work fairly well(still does, never though to change my "habit") but maybe I'm a bit off or I should be counting turns or something...(all else being equal)seems turns might be more accurate...

9/20/2002 2:22 AM
Jason Lollar	Turn count works for me as long as they are both a similar design pickup. Last time I fooled around with it was on some prewar Rick horse shoe pickups, beleive it or not it was really hard to hear a difference between 38 gauge and 42 wound to the same turn count. With more modern designs the wire size makes more of a difference in tone.

9/20/2002 1:32 PM
Mark Hammer	Matching vs matching Different kinds of "matching": for level purposes, for hum-rejecting purposes. Level purposes: I wouldn't knock myself out about it too much, since output will change as a function of PU position, height, etc. If I wound two Strat-type coils with the same gauge of wire, and they measured 7.12k and 7.24k DC resistance, I'd personally consider them "matched" for level. Hum-rejection: HB pickups cancel hum not because the two coils match each other in DC resistance, but because they have the same number of turns and are equally sensitive to the source of the hum. That being said, if you have no set-up to keep accurate track of the number of turns on each coil, DC resistance is a reasonably good approximation. If your coils are matched within 1% of each other on DCR, they will be pretty well closely matched for #turns. Not precisely,, but very close, and certainly close enough to provide decent hum-rejection. If the two coils are of equivalent dimensions but different wire gauges, you can use the resistance-per-foot/metre conversion factor (resistance per unit length is usually found on the spool info, but there are charts available too) to guesstimate #turns. It will be less accurate than using DCR to equate two coils of identical wire, because thicker wire will mean greater circumference for each turn once you're a couple thousand turns into it. Given the greater circumference of a turn, even if thicker wire has a proportionately lower linear resistance, each turn is a little more length than a thinner gauge wire. Again, it will not be WILDLY erroneous to use linear resistance conversion factors to calculate what DCR would represent equivalent # turns for two coils, but it probably won't be as accurate as same gauge wire. Of course if the two coils are of different dimensions it gets even trickier. I doubt you could match a Jazzmaster-type coil and a Strat-type coil for #turns using DCR with any reasonable degree of accuracy. Throw different wire gauge into the mixture, and you've probably entered a zone where there will be no reasonable substitute for a mechanical counting device or manual count tabulation procedure....if you are intending to match them turn for turn for maximum hum-rejection.

9/20/2002 1:32 PM

Mark Hammer

Matching vs matching

Different kinds of "matching": for level purposes, for hum-rejecting purposes.

Level purposes: I wouldn't knock myself out about it too much, since output will change as a function of PU position, height, etc. If I wound two Strat-type coils with the same gauge of wire, and they measured 7.12k and 7.24k DC resistance, I'd personally consider them "matched" for level.

Hum-rejection: HB pickups cancel hum not because the two coils match each other in DC resistance, but because they have the same number of turns and are equally sensitive to the source of the hum. That being said, if you have no set-up to keep accurate track of the number of turns on each coil, DC resistance is a reasonably good approximation. If your coils are matched within 1% of each other on DCR, they will be pretty well closely matched for #turns. Not precisely,, but very close, and certainly close enough to provide decent hum-rejection.

If the two coils are of equivalent dimensions but different wire gauges, you can use the resistance-per-foot/metre conversion factor (resistance per unit length is usually found on the spool info, but there are charts available too) to guesstimate #turns. It will be less accurate than using DCR to equate two coils of identical wire, because thicker wire will mean greater circumference for each turn once you're a couple thousand turns into it. Given the greater circumference of a turn, even if thicker wire has a proportionately lower linear resistance, each turn is a little more length than a thinner gauge wire. Again, it will not be WILDLY erroneous to use linear resistance conversion factors to calculate what DCR would represent equivalent # turns for two coils, but it *probably* won't be as accurate as same gauge wire.

Of course if the two coils are of different dimensions it gets even trickier. I doubt you could match a Jazzmaster-type coil and a Strat-type coil for #turns using DCR with any reasonable degree of accuracy. Throw different wire gauge into the mixture, and you've probably entered a zone where there will be no reasonable substitute for a mechanical counting device or manual count tabulation procedure....if you are intending to match them turn for turn for maximum hum-rejection.

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