I had a niece build a tenor ukulele in my shop. We ended up with an interesting wolf note on the high G string or the A string tuned to a G. Actually a little flat or a little sharp no problem. We put strings on the Uke and strung it up with the neck clamped in a vice as shown in the picture and all of the strings sound great. I took it out of the vice and the G string sound awful it died right away and there was a rattle. Trying to track down the problem I cleaned up the rattle tightening the tuners and cleaning up the nut slot but the G note still just died. It was weird as everything I touched around the neck made the problem go away. Interesting enough while playing a C cord (just fretting the A sting on 3 fret) all sounded great again. A capo clamped on the headstock cleaned it up as well.
With this information I took a spectrum plot tapping the neck with the strings tuned to pitch muting the strings and lightly holding the neck. I have a steep peak right on 392 Hz (that G string).
It is a spanish heel neck. Sort of in the middle of the road for neck thickness. Other than telling her to always have a capo on her headstock, are there other clever solutions. Most of the ones I thought of are invasive, like replace the flat 4 mm rosewood fretboard with an ebony fret board, maybe making it 5 mm sloping to 4.5 mm at the 12 fret to get it heavier and maintain my setup. Or pull the fretboard and install a metal bar in a truss rod slot.
Thanks for any ideas.
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