A note on the low E goes sour. The pitch wobbles a little after you pick it. It dies before it should. Most players blame the strings, change them, and hear the same thing a week later.
The magnet is doing it.
A pickup is a magnet sitting under a steel string. Get it close enough and it stops being a passive listener and starts pulling. Fender's setup guidance puts the mechanism plainly: with the pickups too close, magnetic pull makes the string vibrate in an elliptical pattern instead of a circular one, and you lose tone and harmonics. That elliptical swing is the wobble you hear.
This post is about telling that fault apart from the three that sound like it. It is not a setup guide. If you want the height procedure and the balance rules, those live in the pickup position guide.
The Four Faults That All Sound Like a Bad Note
Four different problems arrive at your ear as the same complaint. This note sounds wrong and dies early.
| Magnet pull | Worn fret or dead spot | Bad nut slot | Dead strings | |
|---|---|---|---|---|
| Which strings | Wound low strings first | Any, usually one | Open strings only | All six about equally |
| Where on the neck | Open and low frets | One fret, repeatable | Open position only | Everywhere |
| What you hear | Pitch wobbles after the attack, note dies early | Buzz on attack, or the note chokes out | Ping or buzz, open note reads sharp | Dull, no top end, sustain is fine |
| Capo at the fifth | Improves | No change | Gone entirely | No change |
| New strings | No change | No change | No change | Fixed |
| Lower the pickup | Fixed | No change | No change | No change |
The last two rows are the whole diagnostic. Only one of the four cares about a pickup screw, and only one of the four cares about a fresh set. Run both and you have your answer in five minutes.
The Capo Test
This one costs nothing and needs no tools.
Play the open low E. Listen past the attack for the wobble. Now put a capo at the fifth fret and play the same string. You are asking a shorter piece of string to do the same job.
A shorter string swings less. Less swing means less time spent down in the strong part of the magnetic field, so magnet pull eases off. If the wobble softens or goes away, the magnet is your problem.
A worn fret does not care about a capo. A dead string does not care. A bad nut slot is out of the picture entirely once a capo is on, which is useful information by itself. If the problem vanishes with a capo anywhere on the neck, look at the nut before you look at the pickup.
Why It Is Always the Low Strings at the Neck Pickup
Two things stack up in the same place.
The wound low strings carry more steel than the plain ones. More steel means more of the string responds to the magnet. That is also why those strings are louder in the first place.
Then there is where the string swings. Fender publishes this point directly in its setup guidance: string vibration is wider at the neck pickup than at the bridge pickup, and you have to compensate for it. The string is near its widest arc over the neck pickup and near a fixed end over the bridge pickup. Same string, same note, very different amount of movement over the two magnets.
Low E, neck pickup. That is where you will hear it first, and it is why the factory numbers set the neck pickup further from the strings than the bridge.
What the Manufacturers Publish
Use these as a starting point. They are not the answer for your guitar.
| Guitar | Position | Bass side | Treble side |
|---|---|---|---|
| Fender Stratocaster | Neck and middle | 2.4mm | 2.0mm |
| Fender Stratocaster | Bridge | 2.0mm | 1.6mm |
| Gibson humbucker | Neck | 2.4mm (3/32 inch) | 2.4mm |
| Gibson humbucker | Bridge | 1.6mm (1/16 inch) | 1.6mm |
Fender measures from the top of the pole piece to the bottom of the string with the last fret held down. Measure it any other way and the number means nothing.
Two things the table cannot tell you. Heavier strings swing wider and need more room. And a hotter pickup pulls harder at the same distance, which is the part most people get backwards.
Higher Output Means More Clearance, Not Less
The instinct with a hot pickup is to back it off because it is already loud. That is right, and for the wrong reason.
A stronger magnet is a stronger pull at any given gap. Set a high output set to the number printed for a vintage set and you have quietly doubled the force on the string. The spec sheet number assumes the magnet the factory shipped.
This is also why a P-90 gets blamed for being muddy when it is really just set too high. The bar magnets sit under the coil, but the field at the string is strong, and a P-90 mounted in a Junior has no pickguard height to hide behind. There is more on how those pickups behave under gain in the P-90 and overdrive guide.
A PAF style humbucker gets off lighter. Its magnet lives under the coils and feeds steel pole pieces, so the string sees a weaker field than it does over a Strat pickup, where the pole pieces are the magnets themselves. Humbuckers are not immune. They just have more room before it bites.
The Part I Had Backwards
I lowered a neck pickup expecting to lose something. Less magnet under the string, less signal, thinner sound. That is the trade you assume you are making.
The note got clearer. Not just longer. Clearer.
What came back was the top end. The magnet had been flattening the harmonics that give a note its edge, and I had been reading that loss as the pickup being dark. I had spent a while chasing it with the amp's treble control, which was the wrong tool for a problem that lived a quarter inch above the pole pieces. Two turns of a screwdriver did what the tone stack could not.
Output went down maybe a hair. I turned the amp up. Nothing else was lost.
That trade is worth knowing about because it runs against how everybody talks about pickup height. Raising a pickup gets described as more output and more attitude. It is also less string.
No Amount of Amp or Modeler Tweaking Fixes This
Worth saying plainly, because it decides where you spend your evening.
Magnet pull happens at the string. It is done before the signal leaves the guitar. A tube amp cannot undo it. A modeler cannot undo it, and neither can a better cab block, a different impulse response, or an EQ curve you spent an hour on. Every one of those is working on a signal that already lost the harmonics.
If a note wobbles into a Blues Junior and wobbles the same way into headphones off an HX Stomp, stop adjusting the rig. The problem is on the guitar.
What To Do This Week
Take the low E. Play it open, listen past the attack, and decide whether it wobbles. If it does, put a capo at the fifth and play it again.
If the capo helped, get a small screwdriver and lower the neck pickup two full turns on the bass side. Play it again. That is usually the whole repair.
If the capo changed nothing, put a fresh set on before you touch anything else. Strings are cheap and they rule out a whole row of the table.
Set the height by ear from there, not by the chart. Fender's own procedure is to drop the pickup well away from the strings, listen to how the note rings with the magnet out of the picture, then raise it until you can hear the magnet start to grab, then back off. The chart gets you close. Your ear tells you when the string is free.
One more thing worth checking while the screwdriver is out. If the wobble only ever showed up on the neck pickup and you have been avoiding that setting for months, you have been playing around a fault instead of fixing it. Where you pick changes which harmonics exist in the first place, and there is more on that here if the neck position still sounds thick after the height is right.
A guitar with one pickup has less of this to go wrong, which is part of the argument for them. That case is made in the single pickup post. But most of us have two or three, and two or three magnets is two or three chances to strangle a string you meant to hear.
