Acoustic Tuning query

What does it say if you play the note at the 12th fret? It sounds like a basic intonation problem, but there's probably not a lot you're going to be doing about it because acoustic guitars tend to have fixed bridges.

How old are the strings? Old strings will sometimes be slightly out of tune at higher positions.

Hi Folks, Can Anyone help in answering this query? After tuning my Acoustic with Electronic Tuner, I've noticed that after doing so, although the tuner says the guitar is in tune to the normal, EADGBE, whenactually I fret a note and play, I notice that the tuner will say that the fretted note is out of tune by probably being slightly sharp . Why should this be so, is it normal , any ideas :?:

Intonation is one thing, but you want to look up something called equal temperament tuning, to understand something about the notion of "perfect tuning".

Short answer: theres no such thing as all strings on the guitar being perfectly tuned on every fret.

Best,

Sean

There can be several causes. In order of likelihood for a beginner, they are:

1. You're accidentally bending a string when you fret the note. It's common for beginners to pull strings down (toward the floor) when they're fretting notes, which bends the string off pitch. This can be very hard to detect, because a beginner's ears often aren't good enough to hear the difference at first. The solution I use with my students is to have them play in front of a mirror - it's hard to see when you're looking down at your hand, but if you're looking head on (in the mirror), you can see the strings aren't evenly spaced when you're fretting.

2. Old strings. The pitch a string produces depends on the tension, length, and mass of the string. As strings get old, they get dirty... which means they gain weight. When that happens, the pitch drops, and we compensate by increasing the tension. The trouble is, the extra mass from finger dirt won't be evenly distributed - so if you fret at the 12th fret, you're now getting 1/2 the string length, but LESS than 1/2 the mass - so the string will sound sharp.

3. Intonation. The very ends of a string don't really vibrate the way the rest of the string does, and the area that can't react fast enough creates a difference between "scale length" (the distance between nut and bridge) and "speaking length" (the part that actually vibrates). This difference gets bigger as a string gets thicker, and it's handled by "string compensation" - making the thicker strings a little longer with adjustments at the saddle - and on some guitars, at the nut as well. On electric guitars and a few acoustics, this speaking length can be adjusted: play a harmonic at the 12th fret, and then fret the string at the 12th fret. If the fretted note is sharp, your bridge saddle needs to be moved back (away from the peghead), and if the fretted note is flat, it needs to be moved forward. But make sure you have new strings on when you adjust the compensation - otherwise the old string factor will complicate things. And make sure when you fret, you're pressing straight down into the fretboard (and not too hard - just enough to get a good clean sound)

I see Sean just posted. What he says is true - in equal temperament, only octaves are truly "in tune". But that's got nothing to do with the result from your tuner - it's "out of tune" at the same rate as the rest of our equal temperament system. A guitar's design will allow you to play reasonably close to "in tune" (i.e. within maybe 1/2 of 1%) on most guitars. That's close enough so that only exceptional ears can hear the difference.

If you really want to get precise about your tuning, you can check out compensated nuts. And if that's not enough, look into fanned frets as well :)

Short answer: theres no such thing as all strings on the guitar being perfectly tuned on every fret.

Fundamentally true, so in response to your "is this normal" question: Yeah, it's normal.

Probably inherent in your question is this one: "Is it a problem?"

Probably, it isn't a problem at all. To be sure, you'll have to rely on your ears, not your tuner. Slight variation in note pitch is normal, on most any instrument, most any note. The question is, is it close enough that it sounds in tune? If you're playing chords, and they sound good, and playing scales, and the intervals sound and feel "right," then for all normal purposes, it's normal.

It would be worth thinking about the things NoteBoat listed to see if there is anything you can/should change. I would add "string height" to his list of things to check. If your strings are too high, you have to push (and therefore stretch) them a little more in order to get them to the frets. Naturally, this gives a slightly sharp note. This effect seems to get bigger as you move towards the body of the guitar, where the strings tend to be higher.

If string height is an issue, a good setup can help.

But if you can't find anything "wrong," and everything sounds good, then don't worry. It's music, not calculus- if it SOUNDS near enough, it IS near enough.

Best,
Ande