What actually happens when you adjust your guitar’s pickup heights?
Of all the free upgrades available to a guitarist, pickup height is the one most people leave on the table. There are no parts to buy and no soldering involved – all you’ll need is a screwdriver and ten minutes. And yet the same players who’ll agonize over capacitor values will happily leave their pickups sitting wherever the factory left them.
READ MORE: Why do guitars have pickup covers and what do they actually do to your tone?
This is, to put it mildly, a shame. Because moving a pickup a millimeter or two can change how a guitar sounds and feels more than a pickup swap does. So before you go reaching for that screwdriver, it’s worth understanding what’s going on under the strings.
Can We Talk About Magnets For A Second?
A magnetic pickup works because your strings are made of steel. The magnets in the pickup throw out a field, and when a string vibrates inside that field it disturbs the flux, which induces a tiny voltage in the coil wrapped around the magnets. That voltage is your signal.
The thing to grasp is that a magnetic field gets weaker very quickly as you move away from the magnet – not in a straight line, but steeply. So the closer the string sits to the pole pieces, the more of that dense field it’s swimming in, and the bigger the signal it generates. Raise the pickup and the output goes up. Drop it, and the output falls away. That’s the part everyone knows, and if output were the only thing in play you’d simply crank every pickup as high as it’ll go and enjoy the extra volume. But it isn’t, and you shouldn’t.
For Every Pro, A Con
Here’s the bit that trips people up. Those same magnets that let the pickup hear your strings are also, gently, trying to grab them. Steel strings are ferromagnetic, so a strong magnet sitting close underneath exerts a real, physical pull on them.
Get the pickup too close and that pull starts to fight the string’s natural vibration. You lose sustain, because the string is being pulled into being centered over each pole piece. Worse, the magnetic tug acts as a second force on the string alongside its own tension, and the two don’t always agree.
The result is a warbling, slightly out-of-tune quality – players often describe notes that “flutter” or beat against themselves, and intonation that wanders even though the saddles are set correctly. Some of the old hands call it “Stratitis,” because vintage-style Strats with their strong Alnico rod magnets are classic offenders.
It’s nearly always worse on the neck pickup. A vibrating string moves furthest from rest near the middle of its length – roughly where the neck pickup lives – so the string is physically closer to those magnets through the swing of its vibration. The bridge pickup sits where the string barely moves, which is part of why it stays clearer even if it is set quite high.
It’s also worse on the wound strings, especially the low E and A, simply because there’s more steel there for the magnet to grab. And when you fret a note at the 12th, the string sits closer to the pickup than it does open, so the higher you play, the more the magnet interferes. If you’ve ever raised a neck pickup for more output and found your guitar suddenly sounds sour on the top frets, that’s exactly what happened.
Here’s A Good Starting Point For Your Setup
Beyond raw output and the pull, height also nudges the character of the sound. Closer pickups tend to sound a touch more compressed and aggressive, with the dynamics squashed slightly. Back them off and you’ll often hear a bit more openness, bloom and dynamic range, at the cost of some level. Neither is “correct” – a player chasing a snarly, in-your-face bridge tone might want it close, while someone after a glassy, bell-like neck sound will usually find it lower down.
The convention is to hold the string down at the highest fret and measure the gap from the top of the pole piece to the bottom of the string. The reason we fret the string is that that’s the worst-case distance and the point where magnetic pull bites hardest.
Manufacturers publish starting points, and they’re a sensible place to begin rather than gospel. For Fender’s single coils, you’re broadly looking at somewhere around 2mm on the treble side and a little more on the bass side, with the hotter, higher-output sets sitting a touch lower than vintage ones to keep the magnetic pull in check. Humbuckers behave more politely – the bar magnet sits below the coils rather than directly under the strings, so the pull at the string is gentler and you can run them closer. Gibson essentially tells you to set them by ear, but somewhere around 1.6mm on the treble side at the last fret is a fair opening bid.
Most techs will set the bass side slightly lower than the treble side; the wound strings have more energy and more steel, so they want a bit more room. Be sure not to set things so high that a hard-strummed string can actually clack against the pole pieces – it’s easy to do on the neck pickup if you’re heavy-handed.
If you’re running active pickups like EMGs, most of this is moot. They use weak magnets and a built-in preamp to do the heavy lifting, so there’s very little pull and height makes far less difference to output. Set them close and forget about it.
The last job is getting your pickups to play nicely together so the volume doesn’t lurch when you flick the selector. Because the neck position is naturally louder, you generally end up with the neck pickup lower and the bridge pickup higher to even them out.
Plug in, switch back and forth between positions while you play, and adjust until the jump in level disappears. It’s fiddly and it’s iterative – raise one and the balance shifts, so you go round again.
Which is really the whole approach in miniature. There’s no single right number on a feeler gauge, only a setting that suits your strings, your magnets, your playing and your ears. Start from the maker’s spec, move in small turns of a quarter-turn or so, and keep playing as you go. The tape measure gets you in the ballpark; the warble, the sustain and the balance between positions tell you when you’ve actually arrived.
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Source: www.guitar-bass.net
