setup question

[Briansol]

I'm having some intonation issues with a fixed bridge guitar.

It has the TOM bridge like a les paul.

open and 12th fret harmonic are on pitch. That tells me that the bridge is good, right?
but fret 1 through 9 are all sharp on the g/b/e high strings. around fret 10 it starts getting closer to pitch.

Can i do anything about it? it's really becoming annoying that I can't get open chords to both sound in pitch /good at the same time. Like if E is good, D is horribly out of tune. If C is good, G is not.

I was running this guitar is Drop C for a long time with heavy gauges (56-11 i think) and i last night i threw 10-46 on it to see if it was a string issue, but its just the same, if not worse with the skinny strings in std tuning.

[Mike]

I tend to set intonation at 2 and 14 to help this, using a super-accurate tuner like a Peterson. Just make sure you're fretting straight.

[lespauled]

Is the nut high? These symptoms usually mean that the nut is cut too high or the wrong scale length.

[Mike]

Is the nut high? These symptoms usually mean that the nut is cut too high or the wrong scale length.

That's a point, 12 to 12 harmonic will tell you pretty quick if the scale length is off.

[Drew]

open and 12th fret harmonic are on pitch. That tells me that the bridge is good, right?

No. You want the 12th fret harmonic to agree to the 12th fret fretted note, not the open string. The 12th fret harmonic is based on the pitch of the open string, those two will always agree - a given harmonic (octave in this case) is always going to sound exactly that interval above the fundamental. When you're setting intonation, you're trying to ensure a fretted octave agrees with the octave produced by a harmonic on the open string, as a way of basically fine-tuning the length of the string to make sure the frets fall in the right place on it, and are at the correct points to create the intervals they're supposed to.

It's been a long time since I've set intonation, actually but I would also always check the 17th fret touch harmonic while fretting at the 5th fret, against just tapping a note on the 17th fret, and if there was any inconsistency between that and the 12th just try to split the difference between the two.

[Budda]

Sounds like the neck is bowed maybe?

[Mike]

No. You want the 12th fret harmonic to agree to the 12th fret fretted note, not the open string. The 12th fret harmonic is based on the pitch of the open string, those two will always agree - a given harmonic (octave in this case) is always going to sound exactly that interval above the fundamental. When you're setting intonation, you're trying to ensure a fretted octave agrees with the octave produced by a harmonic on the open string, as a way of basically fine-tuning the length of the string to make sure the frets fall in the right place on it, and are at the correct points to create the intervals they're supposed to.

It's been a long time since I've set intonation, actually but I would also always check the 17th fret touch harmonic while fretting at the 5th fret, against just tapping a note on the 17th fret, and if there was any inconsistency between that and the 12th just try to split the difference between the two.

Or just fret the notes at 5 and 17 and see what your tuner says. I never understood using harmonics when we have perfectly functional, highly accurate chromatic tuners.

[Briansol]

Thanks, that's good to know i was doing it wrong. So, there may be a chance to get it closer to pitch afterall. I'll report back in a few days. Thanks!

[Briansol]

Is the nut high? These symptoms usually mean that the nut is cut too high or the wrong scale length.

i honestly don't know how to tell.

the action is pretty good, so i don't think so, but i'm not really sure.

[Drew]

Or just fret the notes at 5 and 17 and see what your tuner says. I never understood using harmonics when we have perfectly functional, highly accurate chromatic tuners.

Eh, it's a perfect unison, you could practically do it by ear using a harmonic. And, from a purely mathematical standpoint, using the harmonic is no different from using the fretted note, you're just muting the fundamental and unrelated overtones to come through, and allowing only a very specific, pure overtone to ring. So it's not like you're giving anything up, by doing something that makes the differences more audible.

[Leon]

i honestly don't know how to tell.

the action is pretty good, so i don't think so, but i'm not really sure.

Fret the string against the 2nd fret (so, your finger is in the 3rd fret space), and check the distance from the string to the 1st fret. It should be less than the thickness of the string, roughly.