Understanding intonation

[brianhejh]

Hi Guys.

When setting intonation, I have always tuned the open strings, then set the 12 fret and harmonic, guitar now in tune!. Or so i thought.

Recently I started to identify what seemed to be poor intonation, open strings were perfectly in tune, 12 fret/harmonic in tune however when I fretted frets 1 to 6 they were sharp?.

I then flattened the open strings slightly to allow the first 1 - 6 frets/fretted to play in tune, perfect!. However the open strings are now slightly flat?

My question: Is this were I have read somewhere that it is advised to tune slightly flat? and if so should the process of tuning be: Tune open strings slightly flat in order to achieve correct fretted tuning between the 1st to 6 frets, followed by intonation at the 12 fret to accommodate frets 6 through 12.

Thanks

Brian

[Russ C]

Sounds to me like the nut slots are too high - raising the pitch of every fretted note until you get far enough away from the nut for the saddle compensation to have more effect.

[stanron]

My first thought was that the nut was too high, just like Russ C said. You can check this if you have a capo that matches the fretboard curve.

With the capo on the first fret check your open capo tuning and then check that against the 13th fret and it's harmonics. If they are both in tune then the open string fault is the result of a high nut.

Alternatively take the guitar to a guitar tech and explain your problems.

[JonPR]

I agree with the above. This is a typical symptom of a too high nut (and possibly light gauge strings). When the nut is too high, pressing the strings down to the lower frets stretches them, pushing them sharp. If the action is otherwise good, it's less of a problem on higher frets.
Light gauge strings are also easy to push sharp if you have a heavy touch.

Stanron's capo tip is good. Regardless of the intonation, if the strings feel easier to fret when a capo is placed on fret 1, then your nut is too high. Fretting a string at fret 1 with no capo should feel exactly the same as fretting a string at fret 2 with a capo on 1.

[Lee Callicutt]

You don't need a capo. Depress each string individually between the second and third fret, then tap the string just behind the first fret. Ideally you should hear the slightest metallic ping as the string strikes the fret. If you have to depress the string much more than that to meet the first fret then the nut slots are too high.

Frets.Com has a great illustration of this, but I couldn't get the link to work.

[stanron]

Originally Posted by Lee Callicutt

Frets.Com has a great illustration of this, but I couldn't get the link to work.

http://www.frets.com/FretsPages/Musi...nutaction.html

Here it is. If you are a bit 'Techy' you can loose several hours looking and learning on this site.

[TBman]

You might want to take a look at how James Taylor tunes. Yes, he does some strings a touch flat.




I have a couple of tuners and a tuning fork, but I find I still have to tweak to what sounds best to my ear.

[ljguitar]

Originally Posted by TBman

You might want to take a look at how James Taylor tunes. Yes, he does some strings a touch flat.

Hi TB…

Sweetened tunings (James is sharing his sweetened tuning for his guitar) are an interesting topic.

You do realize that unless your guitar is 'out' the same amount as Jame's guitar, then the sweetened tuning he offers will not work for you? There is not a universally perfect model of how far out of tune different guitars nut/frets/saddle are.

I have my 4 main guitars set up and intonated very closely by an experienced luthier, and yet each requires some tweaking to get them to play perfectly (ha) in tune with themselves.

The compensation on each of the four is slightly different, and I have them intonated with the 6th string dropped to "D" instead of "E" because I play slightly more than half the time in Dropped D rather than standard tuning, and this improved the intonation on the 6th string even more.

Despite all that, I know which strings I need to compensate for when playing chord clusters…and know that individual strings when playing three note inversions on higher frets are more out of tune than lower frets.

They are really close…and with the 1/1000 half step clip-on tuners available, repeatable fudging is possible because the ones I use all indicate when they are slightly flat/sharp to an even finer resolution.

Kick me in the head…
Add a capo…or better yet…another player or an acoustic piano, and we're back to not-so-in-tune-as-one-might-hope. At least my ears are still calibrated pretty closely…

[Mr. Jelly]

I always fretted at the 12 fret against the 12th fret harmonic. If the action is high in some way you pull the strings sharp.