In a similar article “How to Set-Up Your Guitar” we went through how to adjust your guitars action. If you don’t already know how to do this, or haven’t read the previous article I suggest you go back and read it- because it’s important that we set up the action before we adjust the intonation. This article is about adjusting your guitar intonation (how “in tune” the notes are all along the fretboard).
The intonation of a guitar is what makes sure each note is in tune along the neck- this is why it’s important that your guitar neck is pretty straight. All guitar intonation is actually only approximate, and its impossible for a guitar to be 100% accurately in tune on every note.
This is the part when you need your tuner. Assuming that the open strings are still in tune (you will need to tune them if this is not the case), play the harmonic at the 12 fret (place your finger lightly on the string directly over the fret- do not push down). Next, fret the note at the 12 fret of the same string. When the intonation is set properly, these two notes (harmonic and fretted) will be at the same pitch. This is why you may want to use your tuner.
Setting the Intonation
This method works because the harmonic at the 12th fret is always at exactly half the length of the string (from nut to bridge), and so always sounds an octave (twelve frets) above the open string.
If the notes are not the same, you need to adjust the length of the string so that the 12th fret lies exactly half way between the nut and the bridge. This is done by moving the saddles (the part of the bridge that the string first comes into contact with when coming from the nut). If your harmonic is lower than the fretted note it means that the string is too long and needs shortening, and if the harmonic is higher it means that the string is too short and needs to be longer.
Lengthening the string will move the 12th fret closer to the nut than the bridge for that string (because you are moving the bridge further away), and will therefore make the note at that fret lower.
To lengthen the string, find the screws that are set parallel to the neck and connected to the saddles. As you screw and unscrew these screws it will change the position of the saddle (forwards and backwards). To lengthen the string, tighten the screws so that the saddle moves back, away from the neck. The opposite (unscrewing the screws) will shorten the string length and increase the pitch of the note on the 12th fret.
Once the harmonic and fretted note are at the same pitch, you will need to re-tune the string (as length affects pitch). You may need to repeat the process several times to get it right. When you have all the strings in tune and at the correct length you have finished. Well done, your guitar is now set up correctly, and perfectly in tune (or as close as physically possible).
I hope this article has helped you set up your guitar, and made you realize that you don’t need to spend any money to do this! Any questions? Please, don’t hesitate to email me (“Contact” in menu above).