I’m often surprised when I go to a guitar store, or play other peoples instruments how many of them have bad intonation, especially (And here’s the good part!) as it’s so easy to fix yourself.
I’m not going to go into huge scientific detail here, but basically, if your guitar’s intonation is set correctly, it means that no matter where you’re playing on the neck, the notes you play will be in tune, and not flat or sharp.
Now, you don’t want to set your intonation with brand new strings on, or with old ones – if they’ve had a couple of days to settle down, you should be fine.
- Tune your guitar to pitch, using a tuner or whatever your usual method is.
- Play a harmonic at the 12th fret of the string you’re going to set, and check that it’s in tune. (This harmonic is the same note as the open string, only an octave higher.)
- LISTEN to the pitch of the harmonic and keep it in your mind.
- Now fret the same string at the 12th fret and play the note. Is it the same as the harmonic? Or is it slightly lower or higher? Play the harmonic again and double check. You can use a tuner to help with this too.
- If the fretted note is different to the harmonic, you need to set the intonation. Have a look at the bridge of your guitar. The parts of the bridge where the strings cross it are called the saddles. Usually, as on a Strat or Les Paul, there are 6 saddles, one for each string, and each of these is held in place by a bolt whose head you’ll see on the front or back of the bridge. This little bolt moves the saddle backwards and forwards and allows you to set the intonation.
- When you move the saddle, it alters the length of the string that is vibrating between the bridge and the nut of the guitar. As you all know, a shorter string = higher pitch, so if the fretted note at the 12th fret is Lower in pitch than the harmonic, using an appropriate screwdriver for your guitar, turn the bolt so that the saddle moves towards the neck of the guitar, making the vibrating part of the string shorter.
- CHECK YOUR TUNING! Then check the fretted note against the harmonic. If it’s still too low, move the saddle closer to the neck, if it’s higher than the harmonic, move the saddle away from the neck.
- Repeat for all strings.
Regularly check your tuning while setting your intonation, to make sure you don’t drift off pitch.
If your guitar doesn’t have individual saddles e.g. A 3 saddle Tele, or floating jazz box style bridge, the same principal applies, except you may have to ‘split the difference’ between string intonation to get the best overall setting.
Now your guitar should be in tune all the way up the neck, and if you check your intonation regularly you’ll sound better, generally more in tune, and your audience and band mates will thank you!