finger pressure and intonation - tenor guitar

[jazzjune18]

I came across an interesting thing with my new tenor guitar. I tuned it GDAE and therefore have been experimenting with the string gauges. I found that when fretted the first few frets tend to play sharp. Especially with a Capo. After playing around i determined that if i just apply the minimum amount of pressure need to fret, they play in tune, but a capo make it VERY sharp. I am not entirely sure of the physics behind this phenomenon, and if using a lighter, or heavier gauge, string would cause this to be less of an issue while using a capo..

THANKS for any of your suggestions!. you guys (and gals) are the greatest!

Mark

[Bill Snyder]

Your nut is too tall (or at least the slots in the nut are). With the higher nut when you push hard or capo you are stretching the string too far to get it to the fretboard and a sharp note is the result. If you play with a light touch you are only going down to the top of the fret and not stretching the string as far.

[jazzjune18]

Thank you bill. I assumed that may be be case but wasn't sure. I am glad it is something easily fixable. Funny because this guitar came from a reputable online dealer who provides a "professional setup". . I did change the string gauge which needs to be accounted for in the nut slots but it had the same problem with the original strings. Oh well. Setting up your own instrument is part of the fun. Btw. It is a Blueridge and I am very happy with it.

[sunburst]

If it plays in tune with light finger pressure, that indicates that the strings are not necessarily too high at the nut.
Fingers, pressed hard against the strings, or a capo, pressed hard against the strings can pull the strings sharp. The strings stretch as they are pressed into the space between frets down toward the fingerboard, so they go sharp. Minimal pressure does not stretch the strings nearly as much so intonation is better. Lighter strings are more susceptible to this, so using heavier strings can help the situation.
The strings may very well be too high at the nut also (even with the "professional set up" claim), and if so and that is corrected, intonation will be easier to maintain when fretting and/or capoing.

[John Kelly]

What Bill and John say. With a nut that's too high the sharpness of the fretted strings in more evident at the first few frets. is your capo one like the Shubb, which can be adjusted for pressure, or is it one of those that only has one pressure? I like the Shubbs as I can get just enough pressure to get a clean note at the capoed fret, but not so much that the capo pulls the strings out of tune.