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Re: Can I move the pole pieces?
Brando,
"....but it shouldn't have to be that difficult!" But i think it really is not so easy to get it right!
I have found out a little about the more modern Dimarzio stacked humbuckers. This article has a brief explaination (http://www.soundonsound.com/sos/nov9...les/pickup.htm). It says that the top and bottom coils are separated by a magnetic shield to prevent interaction, and that the bottom coil uses its own set of steel cores. Also, the bottom coil needs only about 20% as much wire.
I think that this implies that the steel cores have a much higher permeability than the magnets in the single coil as expected. The idea is to be able to put the dummy coil in series without affecting the sound from the single coil. Thus it should have both a lower resistance and a lower inductance while keeping the same sensitivity to stray magnetic fields. This works because the sensitivity to fields is proportional to the number of turns, while the inductance is proportional to the square of the number of turns, and so the ratio of the inductances will be proportional to the ratio of the number of turns when including the effect of the different permeabilities.
The powerhouse is an active guitar, and so the dummy coil can be added in electronicly. This makes the exact characteristics of the dummy a lot less important.
Brando,
"....but it shouldn't have to be that difficult!" But i think it really is not so easy to get it right!
I have found out a little about the more modern Dimarzio stacked humbuckers. This article has a brief explaination (http://www.soundonsound.com/sos/nov9...les/pickup.htm). It says that the top and bottom coils are separated by a magnetic shield to prevent interaction, and that the bottom coil uses its own set of steel cores. Also, the bottom coil needs only about 20% as much wire.
I think that this implies that the steel cores have a much higher permeability than the magnets in the single coil as expected. The idea is to be able to put the dummy coil in series without affecting the sound from the single coil. Thus it should have both a lower resistance and a lower inductance while keeping the same sensitivity to stray magnetic fields. This works because the sensitivity to fields is proportional to the number of turns, while the inductance is proportional to the square of the number of turns, and so the ratio of the inductances will be proportional to the ratio of the number of turns when including the effect of the different permeabilities.
The powerhouse is an active guitar, and so the dummy coil can be added in electronicly. This makes the exact characteristics of the dummy a lot less important.
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