When adjusting a string saddle and moving it back, making the string effectively longer, does that decrease the sharpness or increase it??

4 Answers 4


I assume you're talking about adjusting a guitar's intonation. You need to compare the pitch of the fretted note on the 12th fret with the harmonic on the 12th fret. If the fretted note is higher than the harmonic, this means that the distance between the saddle and the 12th fret of that string is too short, i.e. you need to move the saddle back such that that distance is increased. If the fretted note is too low, you obviously do the opposite.

  • 1
    Note that the 12th fret isn't some magical intonation fret. I usually check intonation on frets 2 through 7 and 12 through 15 and find that I can't get the whole guitar intonated correctly, so I compromise. Depending on the guitar I might favor the lower frets or the higher frets for best intonation, but usually I try to split the difference. Commented Jan 7, 2016 at 15:40
  • 2
    @ToddWilcox: I agree, but for beginners the 12th fret and its harmonic is usually the easiest way to check intonation. Also, I've noticed that with a decent guitar that is set up well, it's often sufficient to adjust the intonation in the way I've described. If you want to avoid all those intonation issues (once you've set it up correctly), you have to go for True Temperament.
    – Matt L.
    Commented Jan 7, 2016 at 16:38
  • Good point about beginners starting with the 12th fret only for intonation. On that note, I would suggest that, especially for beginners, using an automatic chromatic tuner to check the intonation at the 12th fret will be easier than comparing it to the 12th fret harmonic. I never use the harmonics any more (it would be hard to do that at any fret other than the 12th). Commented Jan 7, 2016 at 16:45
  • It should be pointed out that the amount of pressure applied to the string when fretting a note (especially with jumbo frets) can change the pitch by quite a bit. So it is important to use a normal amount of pressure on the string when comparing the harmonic (unfretted) to the fretted note. "Normal" amount of pressure will vary from one guitarist to the next. It's not an exact science unfortunately. Commented Jan 7, 2016 at 19:16

For a given tension and thickness of string, making the string longer lowers the pitch. If your open string was in tune, but your 12th fret was flat, you would want to shorten the string or lengthen if the 12th fret was sharp.


If a string is sharp, the string needs to be lengthened to flatten it. Conversely, if the note is flat, the string needs to be shortened. So making a string longer makes it flatter, while making it shorter makes it sharper.


this is confusing because of when the term making a string shorter or longer can be done two ways on a guitar. One you can move the saddle forward to the neck which shortens a string and with the same tension makes it flatter. Or you can shorten the string by pulling more tension on it at the tuning pegs. So the statement needs to be qualified that when you move the bridge with the same tension those results happen.

  • Adding tension with the tuning pegs would technically make the string longer, but its speaking length does not change. It definitely does not shorten the string.
    – Edward
    Commented Jul 30, 2023 at 15:06

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.