Seasonal pitch change:

RicB ricb at pianostemmer.no
Sat Mar 10 03:04:11 MST 2007


My experience is that this depends on the season change one is talking 
about.  In humid periods, a bridge swelling that increases the length 
across the bridge evenly for all three strings, will have a greater 
affect on a string of overall shorter length (back length and front 
lengths included) because the bridge surface segment is a larger 
percentage of that overall length. This would mean the right string 
would be sharpest, and the left lowest.  In dry periods.. the opposite 
happens.

What this does not explain tho... is why pitch change happens so 
unevenly across the scale as a whole.  Why do the lowest notes in the 
middle sections seem to have the largest reaction to pitch change, why 
does this pattern more or less reverse itself in the highest section, 
and why does the bass seem much less affected as a whole, but the 
highest notes are the ones most affected there ? I keep getting pointed 
back to something about the two planes (string and bridge surface) 
changing as a whole in relation to each other.

Cheers
RicB


    For me it seems to be the string with the shortest length from the
    capo bar
    to the tuning pin. That string tends to be sharp, while the opposite one
    tends to be a tiny bit flat for me..
    les bartlett



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