ErictheRed
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Changing the pole piece height in your pickups can dramatically affect your sound, so I've created this guide to explain how to best set the pole piece height on standard humbucking pickups. This simple adjustment can do wonders to improve clarity and balance the string-to-string output of your guitar. Why did I feel compelled to write this? Because...
Everyone Gets it Wrong!
I'm amazed at the amount of misinformation out there regarding setting the pole piece height on humbucker equipped guitars, even from respected manufacturers or magazines. Of course we're talking about music and personal preferences, and you may like to set your pole pieces differently than I recommend here. Even so, I hope that you find good, factual information here that can help you to make informed decisions about setting up your humbuckers.
For the thread I'm going to assume that we're working on a Gibson Les Paul, but the information here will hold true for a variety of types of guitars and humbucking pickups, as long as the humbuckers are passive and have adjustable pole pieces.
Your Guitar Should NOT Sound Muddy or Muffled
An extremely common complaint for Les Pauls, especially the neck pickup, is that they sound "muddy" and unclear. This normally leads people to start doing mods such as changing potentiometers, capacitors, and finally the pickups. However, I have NEVER encountered a Les Paul whose "mud" I couldn't clean up by following the advice in this thread. You may want to change pickups for a variety of reasons, but if you're working with a guitar from a reputable company, you should be able to correct this issue.
Wiring and Electronics
I'm not going to discuss various wiring mods or component changes here. However, I recommend using 50s wiring, 500k or 550k potentiometers, and 0.022uF tone capacitors in your guitars. Here's one thread about 50s wiring: https://www.mylespaul.com/threads/wiring-library.558/
Single Coils vs Humbuckers
1. Single-coil pickups generally pull much harder on the strings than humbucker pickups because of their design and geometry (the magnets of a Strat pickup poke up very near the strings, for instance). This guide is NOT applicable to single coil pickups.
2. Humbuckers can be placed much closer to the strings than single coil pickups because their magnets pull the strings less (the magnet lays beneath the windings far from the strings).
Important Info About Electric Guitar Strings
Your guitar strings are NOT created equally! Each string on your guitar is affected by the magnets underneath it differently, and therefore, some strings naturally have more output than others! This is because the solid core of the string is much more dense than the windings, and much more ferro-magnetic. The output of each of your strings depends mostly on the thickness of the solid core. The windings have much less of an impact on output because their geometry creates very high magnetic resistance. If interested in extreme minutiae, search up "Hertzian contact stress" for cylinders.
It's counter-intuitive, but the G-string is the loudest of your strings. This is because it's the string with the thickest core (it has no windings, so you can consider the entire string the core). It's hard to find information regarding core thickness from all string manufacturers, but generally speaking, string output (core thickness) for most electric guitar strings goes like this:
Most Output to Least Output: G - Low E=B - A - High E -- D (approximately).
The G-string has the most output, followed by the Low E and B strings, then the A string, then the High E, and lastly the D string. Some of the in-between strings can be fairly close in output, but generally the G string has by far the most and the D string has by far the least output of any strings for the vast majority of sets.
What NOT to Do
One of the most common recommendations regarding pole piece height is to follow the curvature of the fretboard (in fairness this probably worked well back in the 50s and 60s with wound G strings). This seems to make sense at first; you are trying to get all of the pole pieces the same distance from the strings. Here is one picture of a pickup that does this:
However, we should know now that this is incorrect! It's not too far off for the three lower strings, but you will have a hugely pronounced G-string and quieter high E string if you set your pole piece heights this way.
Finally, How to Set the Pole Piece Heights on Your Guitar
First, you probably want to lower your pickups if you're having problems with mud. You can always raise them higher up later to get more output, but lower pickups in general have more clarity.
Start with each pole piece approximately flush (or a little above) with the pickup cover, or with the head of the pole piece screw just poking above the bobbin on uncovered pickups. Now to measure the pickup height, fret the last fret of the low E string and measure the distance from the low E string to the top of the pickup pole piece. Repeat with the high E string. The treble side of the pickup should be higher than the bass side by about 1/32". A good starting point is to set the bridge treble side to about 2/32" from the high E and the bass side to about 3/32" from the low E.
Now, use your ears to lower the neck pickup (which will naturally be louder at the same height, because the strings vibrate a larger distance here) so that it is at the volume that you want. If you want an approximately equal neck volume to your bridge volume, assuming that you don't have very unbalanced pickups, then the neck pickup will be significantly lower than the bridge. That's OK!
Now that our pickups have approximately the same volume (or whatever amount of imbalance you want), our goal is to set the string-to-string output. This is done by adjusting the pole piece height. In order to achieve approximately equal string-to-string volume, you need to lower the pole piece of the louder strings and raise the pole pieces of the quieter strings. You can do this entirely by ear or use a decibel meter or recording interface if you want to get really precise (though I wouldn't bother).
You most likely want the G-string lowest because it is naturally the loudest, and the D-string highest because it's naturally the most quiet. Therefore, I usually set up my pole pieces to roughly go:
I often use this as a starting point and adjust slightly by ear, because I find that it works well for typical humbucking pickups.
Edit on 3/11:
Raising and Lowering the Pickup vs Pole Pieces, and a Little on How This Works:
Based on some other threads around the forum, I've decided to add a little more info here.
Like many things (gravity, light) that have a source and propagate three dimensionally through space, magnetic fields and the strength of magnetic interaction varies according to the Inverse-Square Law with respect to distance. This means that if you double the distance between two objects, the magnetic force between them becomes 1/4 the original value (weaker by a factor of 4). If you cut the distance to a third (get three times closer), the force becomes nine times stronger! Quadruple the distance and you get a difference in magnetic force of sixteen times the original amount, etc. Clearly the magnetic field varies quite substantially with distance. If you have a pole piece set 4/32" away from a string for instance, and then raise it to 3/32" away, the string experiences a pretty significant increase in strength of the magnetic field.
Anyhow, let's imagine a pickup whose pole pieces are set flush with the slugs. In this case, the slug and pole pieces have essentially the same influence on the strings, as they are the same distance away. If you raise and lower the entire pickup, you increase or decrease the magnetic interaction with the strings in both coils of the humbucker by essentially the same amount. Move the humbucker closer to the strings and you get more output, but often less clarity, and vice versa.
When you raise an individual pole piece, you are increasing the magnetic influence of that pole piece on the string, which makes that string more loud. However the cool thing is, the increase in volume comes primarily from the coil with the adjustable pole piece! This is the coil that surrounds that pole piece, and hence the coil that is affected most strongly by it.
If you raise the pole pieces, the extra output that you get comes mostly from the adjustable coil, and so your humbucker is slightly unbalanced now. Importantly, it is NOT out of phase with the other coil. It's just a little louder, so you don't get any phasing issues. Since you can make one coil interact more strongly with your strings than the other, you can use this to achieve a slight single coil sound. In other words, more clarity and "openness," with less compression. Conversely if you want more output and compression, you can level the pole pieces and raise the entire pickup.
I hope that this guide helps you! Cheers,
ErictheRed.
Everyone Gets it Wrong!
I'm amazed at the amount of misinformation out there regarding setting the pole piece height on humbucker equipped guitars, even from respected manufacturers or magazines. Of course we're talking about music and personal preferences, and you may like to set your pole pieces differently than I recommend here. Even so, I hope that you find good, factual information here that can help you to make informed decisions about setting up your humbuckers.
For the thread I'm going to assume that we're working on a Gibson Les Paul, but the information here will hold true for a variety of types of guitars and humbucking pickups, as long as the humbuckers are passive and have adjustable pole pieces.
Your Guitar Should NOT Sound Muddy or Muffled
An extremely common complaint for Les Pauls, especially the neck pickup, is that they sound "muddy" and unclear. This normally leads people to start doing mods such as changing potentiometers, capacitors, and finally the pickups. However, I have NEVER encountered a Les Paul whose "mud" I couldn't clean up by following the advice in this thread. You may want to change pickups for a variety of reasons, but if you're working with a guitar from a reputable company, you should be able to correct this issue.
Wiring and Electronics
I'm not going to discuss various wiring mods or component changes here. However, I recommend using 50s wiring, 500k or 550k potentiometers, and 0.022uF tone capacitors in your guitars. Here's one thread about 50s wiring: https://www.mylespaul.com/threads/wiring-library.558/
Single Coils vs Humbuckers
1. Single-coil pickups generally pull much harder on the strings than humbucker pickups because of their design and geometry (the magnets of a Strat pickup poke up very near the strings, for instance). This guide is NOT applicable to single coil pickups.
2. Humbuckers can be placed much closer to the strings than single coil pickups because their magnets pull the strings less (the magnet lays beneath the windings far from the strings).
Important Info About Electric Guitar Strings
Your guitar strings are NOT created equally! Each string on your guitar is affected by the magnets underneath it differently, and therefore, some strings naturally have more output than others! This is because the solid core of the string is much more dense than the windings, and much more ferro-magnetic. The output of each of your strings depends mostly on the thickness of the solid core. The windings have much less of an impact on output because their geometry creates very high magnetic resistance. If interested in extreme minutiae, search up "Hertzian contact stress" for cylinders.
It's counter-intuitive, but the G-string is the loudest of your strings. This is because it's the string with the thickest core (it has no windings, so you can consider the entire string the core). It's hard to find information regarding core thickness from all string manufacturers, but generally speaking, string output (core thickness) for most electric guitar strings goes like this:
Most Output to Least Output: G - Low E=B - A - High E -- D (approximately).
The G-string has the most output, followed by the Low E and B strings, then the A string, then the High E, and lastly the D string. Some of the in-between strings can be fairly close in output, but generally the G string has by far the most and the D string has by far the least output of any strings for the vast majority of sets.
What NOT to Do
One of the most common recommendations regarding pole piece height is to follow the curvature of the fretboard (in fairness this probably worked well back in the 50s and 60s with wound G strings). This seems to make sense at first; you are trying to get all of the pole pieces the same distance from the strings. Here is one picture of a pickup that does this:
However, we should know now that this is incorrect! It's not too far off for the three lower strings, but you will have a hugely pronounced G-string and quieter high E string if you set your pole piece heights this way.
Finally, How to Set the Pole Piece Heights on Your Guitar
First, you probably want to lower your pickups if you're having problems with mud. You can always raise them higher up later to get more output, but lower pickups in general have more clarity.
Start with each pole piece approximately flush (or a little above) with the pickup cover, or with the head of the pole piece screw just poking above the bobbin on uncovered pickups. Now to measure the pickup height, fret the last fret of the low E string and measure the distance from the low E string to the top of the pickup pole piece. Repeat with the high E string. The treble side of the pickup should be higher than the bass side by about 1/32". A good starting point is to set the bridge treble side to about 2/32" from the high E and the bass side to about 3/32" from the low E.
Now, use your ears to lower the neck pickup (which will naturally be louder at the same height, because the strings vibrate a larger distance here) so that it is at the volume that you want. If you want an approximately equal neck volume to your bridge volume, assuming that you don't have very unbalanced pickups, then the neck pickup will be significantly lower than the bridge. That's OK!
Now that our pickups have approximately the same volume (or whatever amount of imbalance you want), our goal is to set the string-to-string output. This is done by adjusting the pole piece height. In order to achieve approximately equal string-to-string volume, you need to lower the pole piece of the louder strings and raise the pole pieces of the quieter strings. You can do this entirely by ear or use a decibel meter or recording interface if you want to get really precise (though I wouldn't bother).
You most likely want the G-string lowest because it is naturally the loudest, and the D-string highest because it's naturally the most quiet. Therefore, I usually set up my pole pieces to roughly go:
I often use this as a starting point and adjust slightly by ear, because I find that it works well for typical humbucking pickups.
Edit on 3/11:
Raising and Lowering the Pickup vs Pole Pieces, and a Little on How This Works:
Based on some other threads around the forum, I've decided to add a little more info here.
Like many things (gravity, light) that have a source and propagate three dimensionally through space, magnetic fields and the strength of magnetic interaction varies according to the Inverse-Square Law with respect to distance. This means that if you double the distance between two objects, the magnetic force between them becomes 1/4 the original value (weaker by a factor of 4). If you cut the distance to a third (get three times closer), the force becomes nine times stronger! Quadruple the distance and you get a difference in magnetic force of sixteen times the original amount, etc. Clearly the magnetic field varies quite substantially with distance. If you have a pole piece set 4/32" away from a string for instance, and then raise it to 3/32" away, the string experiences a pretty significant increase in strength of the magnetic field.
Anyhow, let's imagine a pickup whose pole pieces are set flush with the slugs. In this case, the slug and pole pieces have essentially the same influence on the strings, as they are the same distance away. If you raise and lower the entire pickup, you increase or decrease the magnetic interaction with the strings in both coils of the humbucker by essentially the same amount. Move the humbucker closer to the strings and you get more output, but often less clarity, and vice versa.
When you raise an individual pole piece, you are increasing the magnetic influence of that pole piece on the string, which makes that string more loud. However the cool thing is, the increase in volume comes primarily from the coil with the adjustable pole piece! This is the coil that surrounds that pole piece, and hence the coil that is affected most strongly by it.
If you raise the pole pieces, the extra output that you get comes mostly from the adjustable coil, and so your humbucker is slightly unbalanced now. Importantly, it is NOT out of phase with the other coil. It's just a little louder, so you don't get any phasing issues. Since you can make one coil interact more strongly with your strings than the other, you can use this to achieve a slight single coil sound. In other words, more clarity and "openness," with less compression. Conversely if you want more output and compression, you can level the pole pieces and raise the entire pickup.
I hope that this guide helps you! Cheers,
ErictheRed.
Last edited:
