Intonation refers to a guitar’s ability to stay in tune in different positions. As you move up the fretboard on your guitar, the spaces between frets become narrower, and occasionally the notes will not be in tune like they are on the lower frets. This is a telltale sign that your intonation is off. Adjusting intonation can be a little tedious at first, but with some patience and practice, it will save you money not having to go to a repair shop, and build your confidence with repairing guitars.
Some guitar players just notice when their guitar sounds “off” even though it has been tuned. If you are like me, and do not have perfect pitch, you have to grab your favorite tuner to tune your guitar. Tune the guitar however you like, and then check the pitches at the 12th or 14th fret. If you see that the notes are perfectly in tune, your intonation is good, but if the notes become sharper or flatter as you move up the fretboard, you have to adjust. The reason this happens is because the distance between the nut and 12th fret is not the same as the distance from the 12th fret to the bridge. Ideal intonation exists when these two spaces are equal. If the higher notes are sharper, distance to the bridge needs to be increased, if the notes are flatter, distance needs to be shortened. This is most commonly done by adjusting the saddles on your guitar’s bridge.
Here I will be showing how to adjust a Tune-O-Matic bridge. These are equipped on most Les Pauls, SG’s, some Fenders, and nearly all Schecters. Although you may not have this bridge type, the same principle applies.
If you take a closer look at the bridge, you will see that each saddle sits independently, and can be moved closer or further with a simple Phillips head screwdriver.
This is what your bridge should look like, and since my intonation is too flat, I have to bring my saddles closer to the head of the guitar.
Once your guitar is in tune, and you know if the higher notes are sharp or flat, it is time to adjust the bridge. To do this you are going to have loosen one string so that you can reach the screws on your bridge. It is easier to do this one string at a time.
Take the screwdriver and move the saddle closer or further depending on what you need. Once you have done that, place the string back on the saddle and tune it back up. Check the higher frets to see if they are in tune. Be aware that it may not be exact, so you will have to loosen the string and adjust the saddle again. Keep doing this until your tuning gets as precise as possible. For your first time, this may take about half hour to get t done, but once you are familiar with adjusting intonation, it can be done as quickly as 10 minutes.
Now you can play your guitar without hearing certain chords and notes sound dissonant and out of tune.
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