I do my own setups, and make my own custom nuts and saddles. My early attempts were so poorly done, I became an expert on what can make a guitar buzz. Now I'm so precise, I can adjust string height to address the difference in wrist angle between downstrokes and upstrokes with a pick.
If the guitar buzzes with a capo, the nut has nothing to do with it. A nut that is too low, or has string slots cut too deep, will only buzz with open strings. A nut that is too high will cause you to push down too hard on the strings and make the notes go sharp.
Check nut height by pressing the low E string between the nut and the first fret with your left index finger, and between the third and fourth frets with your left pinky or ring finger. Then tap the string between the second and third frets with your right index finger. This should reveal a slight, but noticeable, gap between the string and the second fret.
Then repeat the process by pressing the low E string between the second and third frets with your left index finger. Then tap the string between the first and second frets with your right index finger. This should reveal a gap between the string and the first fret.
If the gaps above the first and second frets are identical, the nut is the proper height. If the gap above the first fret is greater, the nut is too high. If the gap above the first fret is less, or if there is no gap at all, the nut is too low or the string slot is too deep.
Repeat for all buzzing strings.
A poorly shaped saddle or nut slot can produce the sitar effect, but you say that's not the issue.
Buzzing on fretted notes can be caused by insufficient neck relief, too low of a saddle, or uneven frets. A typical setup doesn't involve fret leveling, and a new guitar shouldn't need it.
First, check the frets with a straight edge placed across 3 adjacent frets. It should never rock. If it does, then the middle fret is too high and the neck was assembled improperly.
If the frets pass the straight edge test, loosen the truss rod in 1/4 turn increments until all of the buzzing goes away. This will eventually work, but it may overly bow the neck. If so, the saddle is too low.
If the saddle is too low, place shims under the saddle or have a new saddle made.
Buzzing is never caused by a nut or saddle being too high, or by too much neck relief.
That's about it.
|