A guide to getting your guitar set up properly

A setup is not a tune-up and it is not a repair. It is a set of adjustments that put a specific instrument, strung with a specific gauge, tuned to a specific pitch, into a state where it plays evenly along the whole neck and stays in tune with itself. Every one of those adjustments interacts with the others, which is why the order matters and why doing one of them in isolation usually makes things worse.

What follows is what a bench actually does, in sequence, with the reasoning. It will tell you whether your instrument needs work and whether the work you were quoted makes sense. Some of it you can do at home. Some of it you should not.

Before anything: new strings, and let it settle

A setup is done to the strings the instrument will be played with. Change gauge and every measurement below changes, because a heavier set pulls harder on the neck and needs more clearance to vibrate freely. Tell whoever is doing the work what you use and what tuning you play in. Somebody who plays in D standard with 11s has a fundamentally different instrument to somebody in E standard with 9s, even if they own the same model.

Fit the strings, tune to pitch, and let the neck settle before measuring anything.

1. Neck relief

A guitar neck should not be perfectly flat. A vibrating string moves in an arc, widest near the middle of its length, so the neck needs a very slight forward bow to give it room. That bow is relief, and it is adjusted with the truss rod.

To read it: hold a string down at the first fret and at the fret where the neck meets the body, so the string becomes a straight edge. Look at the gap over the seventh or eighth fret. On most electrics you want something between the thickness of a business card and roughly twice that. Some flat, some more. It is a small number, and the difference between right and wrong is smaller than most people expect.

Too little relief and the strings buzz in the middle of the neck. Too much and the action climbs in the middle registers no matter how low you set the saddles.

The truss rod adjustment itself is a small movement — an eighth of a turn is a real change. Turn it in small increments, retune, and wait between adjustments; wood moves slowly. If the rod is stiff, at the end of its travel, or the neck does not respond, stop. That is a bench job and forcing it is how truss rods break.

2. Action

Action is string height at the twelfth fret, and it is the adjustment players think a setup mostly consists of. It comes third in importance and second in sequence, because relief has to be right first — otherwise you are setting a height against a curve you are about to change.

Low action is easier to play and buzzes sooner. High action is cleaner, louder acoustically, and harder work. Neither is correct. A slide player wants height. Someone playing fast legato lines wants the opposite. The right action is the lowest height at which your playing does not produce buzz, and that is a function of how hard you hit the strings.

Note the qualifier: it depends on the frets being level. If a guitar buzzes at one particular fret on one particular string, that is not an action problem. That is a high fret, and lifting the whole instrument's action to hide it is the wrong fix. Fret levelling is bench work.

3. Nut slots

The nut is where most badly set up guitars are actually badly set up, and it is the least visible.

Each slot should hold the string just clear of the first fret — clearance measured in fractions of a millimetre. Cut too high, and the string has to be pushed a long way down to fret, which pushes it sharp. That is why some guitars play in tune everywhere except the first three frets, and why players sometimes chase intonation at the bridge for a problem that lives at the other end of the neck.

Cut too low and the open string rattles on the first fret, and there is no adjustment that fixes it — the slot has to be filled or the nut replaced.

The slot also has to match the string. Too wide and the string moves sideways in it and pings out of tune when you bend. The back edge should slope down toward the headstock so the string breaks over a defined point, and the slot should be smooth. A string binding in a rough slot is the most common cause of a guitar going sharp after a bend and staying there.

Nut work is done with gauged files and cannot be done properly with anything else. This is the part to hand over.

4. Intonation

Intonation is the compensation that makes a fretted note match the open string an octave below. Pressing a string down stretches it slightly, which raises the pitch, and the amount depends on string gauge, action height and how hard you press. So intonation is set last, after everything that affects it.

Compare the fretted twelfth-fret note against the twelfth-fret harmonic. Fretted sharp means the string needs to be longer, so the saddle moves back, away from the neck. Fretted flat means the opposite. Retune between every adjustment, because moving the saddle changes the tension.

Two things worth knowing. First, a guitar cannot be perfectly in tune everywhere — equal temperament is a compromise and fretted instruments are a compromise on top of it. Second, if a string will not intonate within the saddle's travel, something else is wrong: a worn string, a bridge in the wrong place, or a neck that has moved.

5. Everything else

A full setup also covers pickup height, which affects output balance and, if set too close, pulls the strings out of tune magnetically; tremolo spring tension where fitted; a check of the frets, the electronics, the tuners and the truss rod's remaining travel; and a clean and polish of the fretboard.

Why Texas changes all of it

Wood responds to moisture in the air. It swells when the humidity is high and shrinks when it is low, and the fretboard and the neck do not move at the same rate. In Central Texas the annual range runs from humid spring and autumn air to bone-dry stretches of winter heating and summer air conditioning, and it can swing across days rather than seasons.

The consequences are predictable:

• Dry conditions shrink the fretboard, which leaves fret ends standing proud at the edge of the neck — sharp to the hand, and a reliable early warning. Relief usually drops, and buzzing follows.
• Humid conditions swell the fretboard, which adds relief and lifts the action. The instrument feels stiff and plays high.
• Acoustics react far more than solid-bodies, because the top is thin and under tension. A dried-out acoustic can sink at the bridge or crack.

The practical advice: keep the case humidified in a dry spell, never leave an instrument in a car in an Austin summer, and expect to need a truss rod adjustment two to four times a year rather than once. A guitar that plays perfectly in April and badly in August has not developed a fault. It has responded to the weather, which is what wood does.

When to stop and take it in

Do it yourself: string changes, pickup height, saddle height on a bridge with individual adjusters, small truss rod corrections if the rod turns freely.

Take it in: nut slots, fret levelling or dressing, buzzing that persists after relief and action are right, a truss rod that is stiff or maxed out, structural cracks, and anything on an acoustic involving the bridge or the neck angle.

Guild members receive one professional setup a year as part of membership, and member pricing on everything above. The rest of the world is welcome at the bench too.