Instruments for Professionals
Realize Your Potential
When a guitar is set up properly:

The guitar will feel and sound its best
all the strings will sound with exactly the notes they are supposed to
all notes will sound correct when played at each fret up and down the neck
the guitar will be as easy as possible to play
strings will break less frequently.
If a guitar plays easily and sounds its best then it's easy for the player to feel the music.


When a guitar is not set up properly:

The guitar may not feel or sound quite right
some notes may sound correct while some others may sound sharp or flat
the guitar may be difficult to play
strings will break more often.
What difference does a set up make?
When to Set Up?
How to get a Set Up
Adjusting action at the bridge

Adjustments

Adjusting action at the bridge:
The bridge saddles should be lowered if the string action is too high, that is, the strings are too far
up off the fretboard. In some cases it may be desirable to raise the saddles for a higher string action.

Lower the saddles too much and the strings might rattle against certain frets (this may or may not
be inconsequential on an electric guitar; listen through an amplifier). In more extreme cases,
pressing a string against one fret might actually fret the string against a different fret, usually the
one under the intended one. In both cases, filing the frets might alleviate the problem if the saddle
really should be that low. Otherwise, simply raising the saddle a small amount on the side with the
problem should be fine.


Filing frets
Filing frets should only be done by a qualified repair person and only to correct problems with frets
buzzing or strings being presssed at the wrong fret (see "adjusting action at the bridge", above).


Filing the nut
Filing the nut should only be done by a qualified repair person and is used to reduce pressure at the
nut to allow a heavier gauge of strings to be used.


Neck/truss rod adjustment
This particular adjustment has been known to ruin guitars when performed incorrectly, so here
referral to a professional repair person is highly recommended. A guitar will need a truss rod
adjustment if the neck is not straight. One way to check the straightness of the neck is to play 12th
and 19th harmonics on the low and high strings. After sounding each harmonic, fret the note there
and play it again: it should be exactly the same pitch. If it is not, the neck may be in need of
adjustment. However, this may be indicative of an intonation problem as well,  give the guitar to a
repair person.


Adjusting intonation
You may notice each string on the bridge sits in a "saddle". Depending on your setup, you might
notice the saddles may be in different positions: some might be pushed forward and others might be
pushed back, sometimes slightly. The positioning of the saddle effectively changes the length of the
vibrating string. Tune the guitar to concert pitch with the aid of an electronic tuner, making sure the
open strings are perfectly in tune. Play the 9th and 12th fret harmonics, then play the fretted notes.
If the fretted notes are sharp, the string is too short and the saddle needs to be pushed back toward
the base of the bridge. If the note is flat, the string is too long and the saddle needs to be pushed up
toward the nut. Repeat this procedure for each string. Adjusting the intonation should be done every
few months or at least twice a year.