Humbucker question

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Hello,

I have a question about humbucker pickups.

Simply how are they constructed?

I know that they are two coils connected together. However the point I'm struggling with is the anti phase part.

Taking the view that a humbucker consists of 2 individual coils, how are they connected?

To wire them in antiphase does one need to be wound clockwise and the other anticlockwise then connected if so how?

Many thanks!
 
That doesn't really explain humbucking.

Here's how I understand it, and I hope it's close to correct, as I'm not an EE or anything; I'm really a software geek.

Imagine a long magnet with two identical coils on it one near each end, wound and wired the same. A string near one end acts like a bit of core focusing that flux within its metal, and "improves" the magnetic structure when the string moves close, and makes it worse when it moves away. It's that change in flux that induces a current in the coils. By the right-hand rule, and because we know them to be identical, the coils generate a small signal that is in-phase. This would be a strat pickup for a 1-string guitar.

Now just bend that into a "U" shape like a horseshoe magnet, so that one coil is on one leg and the other coil on the other leg. When a string located close to one or (even better) both ends moves closer or farther, it is not "pushing" or "pulling" flux or electrons or something "into" both ends, it is still just modulating the flux when nearer or farther (to both poles now, which makes it a bit more complex), "improving" the structure when nearer. The coils are still wired the same, the same right-hand rule applies...so the coils still generate in-phase. It's just like before, except now the string is moving near both ends. But now consider a stray environmental magnetic field that washes over the whole thing. Since bending the structure into a "U" it would induce out-of-phase currents in the two coils because they now physically face opposite directions. So now there's a difference between flux moving within the structure of horseshoe and air gaps and string, which moves circularly modulated by the air gaps and goes up one leg and down the other (making music)...versus a stray environmental flux field moving over the whole thing, which moves down both legs simultaneosly or up both legs simultaneously (inducing oposed hum signals which cancel electrically).

Reality is always more complicated than a simplified model but I hope I'm conveying the basic idea, and that I got it right.

Note that the humbucking coil doesn't have to also be near the string. In some microphones you can just add another coil outside the real magentic structure and orient it, and wire it, and adust intensity to cancel hum. But if you can "bend the structure" to also improve detection performance by using both ends, it keeps the ratio of signal to impedance reasonable, so the added inductance of the second coil doesn't kill the treble.
 
There's other ways of making humbucking pickups.

Some have a magnetic structure shaped like an "E" (three leg extensions and two spines). The magnetic fields are the same at the two outer legs, and opposed in the middle. If you put one coil on each segment of the spine, out of phase, you have another humbucker, but with 3 places the string modulates the air gap and flux. There are some really big pickups made like this. Small Lace Sensors are related.

I just got a set of Lace Alumitone pickups. I'm still figuring out the details, but really interesting!
 
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