not a trick question.In all honesty I don't exactly no what hum cancelling means.. can some explain fully what hum cancelling pickups are?
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hum cancelling ??
- Thread starter Nykki Madd
- Start date
Hum cancelling means that you have two coils wound in opposite directions, but with the magnets oriented oppositely, as well. How does this work? Firstly, you wind the coils in opposite directions, so that they can have a 180 degree phase difference. This means that when one coil is on a positive cycle, the other coil is at the same amplitude on a negative cycle. The sum of the two equal but opposite amplitudes is zero. (Think of it like having two people playing tug of war. If the force on each end of a rope is equal, the rope doesn't go anywhere.) Now your pickup is nice and quiet with no hum, but you have a problem. The hum is gone, but so is the signal that you are trying to transduce from string movement. That's why the magnets must be oppositely oriented. If you flip one set of magnets, then the disturbances in the magnetic fields of the two coils will be in different directions, and the result of this is another 180 degrees of phase difference. Since the coils are wound in opposite directions, the effect of flipping the magnets is cancelled out, taking you back to having your signals in phase with each other. So that just leaves one question. Why does the signal induced from string movement stay in phase, but not the signal induced from 60z hum emissions? 60Hz hum does not depend on the magnetic field in the pickup. It is induced directly into the coils.
To summarize what line6man said, a coil of wire is basically an antenna for electro-magnetic interference, especially from the lights and other electrical things in the building. Hum canceling pickups will block out any interference that is picked up by the coils in your pickups and leave what is picked up by the magnets (so to speak) through the process that line6man explained.
They cannot remove hum from grounding problems, or any hums that originate outside the guitar (hum in your amp or effects, for example).
They cannot remove hum from grounding problems, or any hums that originate outside the guitar (hum in your amp or effects, for example).
well that describes the technical part of it and thank you for that.i appreciate it a lot. can you describe like the sound though. a "hum" and "no hum" if that makes sense??
It really isn't a huge deal. Live, just turn down you volume when not playing, and when recording, a noise gate ought to take care of it.
It's completely unnoticeable while playing. It's nice to have hum cancelling pickups, but it doesn't matter too much.
and PS, what line6man posted is 60hz hum, which typically comes from the lights. There are other sources of interference as well, and they sound different. Very poorly shielded pickups can even pick up radio stations! (Rare, but I've experienced it).
It's completely unnoticeable while playing. It's nice to have hum cancelling pickups, but it doesn't matter too much.
and PS, what line6man posted is 60hz hum, which typically comes from the lights. There are other sources of interference as well, and they sound different. Very poorly shielded pickups can even pick up radio stations! (Rare, but I've experienced it).
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It's hardly "going out of your way." If you are not dead set on particular tonal qualities inherent to single coil pickups, there are a plethora of humbuckers on the market, and many even voiced to sound very similar to certain single coil pickups. It just comes down to which pickups you select.
Agreed. If I have a choice, I always go hum cancelling. I'm just saying it's not a big deal if I'm using a split coil or a stock J bass and I experience a bit of hum. My favorite position on my favorite guitar happens to be split coil sound, so hum is part of my life. If I could get the same sound w/o hum, it would be a no-brainer!
