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View Full Version : Scatter-Winding in Pickups.



DrNomis_44
11-02-2016, 01:34 PM
Hi everyone, thought I would start a thread on this topic.


Here's my take on Scatter-Winding in guitar pickups, I've been dabbling in electronics since I was 13 years old so I have some background in it, anyway, so basically what is a pickup?, a pickup is typically a number of turns of very fine enameled-copper wire wound on a former, or bobbin, with a magnetic metal core, in electronics a component that consists of a number of turns of wire around a metal core is called an Inductor, a typical example is an Iron-Cored Choke as used in Guitar Amplifiers, I won't go into the theory behind how Inductors work, or why they are called Inductors because the mathematics is a bit complex.


Okay, so why do some pickup makers wind their pickups using scatter-winding?, my theory is that it is to reduce an effect called Stray Capacitance, when you wind the coils in a pickup in a neat, uniform, and orderly way, you end up with turns of wire sitting adjacent to each other, because the wire is a conductor it form one of the parts of a capacitor, a capacitor is an electronic component that consists of two pieces of electrically conductive material separated by an insulating material, in this case, the air between the coil windings, so what you effectively have is a very low value capacitor in parallel with each coil-winding, this forms what's called a "Tank Circuit", or a parallel LC Resonant circuit (L is the symbol for inductors, and C is the symbol for capacitance in electronics), so why is this resonance due to stray-capacitance bad for guitar pickups?, it's because that any resonances within a pickup will cause a big spike in the response of a pickup and in some cases the pickup will actually feedback at the frequency where the spike occurs even if the pickup has been wax-potted, to get around this pickup makers started scatter-winding their pickups so that the turns of wire wouldn't be adjacent to one another, the end result is that the stray capacitance would be reduced which would then reduce resonant spikes in the pickup response.