Outrageous pickup idea ?

[DeanSweden]

I'm not sure this would work, but, since you can make a
magnet-like structure with a battery, some steel and some
copper wire ... wouldn't it be possible to hook the battery up
to a pot, to controll the voltage coming out and thus making
a weaker/stronger magnet for the rest of the pickup structure ?

[super rad stuff]

i think i've heard of this idea before, and it not being great because there would be too much magnetic energy causing sustain and tone loss since the strings wouldn't be able to vibrate correctly.

[mudpuppy]

Have to disagree w/ srs on this. There shouldn't be any reason you couldn't use and electromagnet vs. permanent in a pickup. It's probably totally impractical with a battery; would probably drain a 9V in a couple minutes. If you used an external power source, it would need to be very well filtered.

Edit: The idea of being to adjust the strength of the magnetic field is not bad. It would probably be a lot easier to simply change the geometry of the permanent magnet. Something like an adjustable air gap.