Hi Ragerio,
Changing the F will have little effect, just go with what you get.
Changing the A up one cent will stretch the middle section just a bit
more.
Changing the C down 1 or 2 cents will stretch the treble less.
I get unhappy if I see F much over 12, but it does happen. I don't like
A much of 8 but will not change it if it is, and I like C in the 5.5 6.5
range and will lower it if it is a lot higher.
Also if I get any measurement less than 5 in F or A I will increase them
some. If I get a C under 4 I will bring it up to about 5.
Just plain practical tuning experience.
Hope this is helpful.
Newton
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