[CAUT] Wire Stretch

[RicB]

This all makes quite a bit of sense given the fact that a change in the 
hight of the string relative to the bridge pins effects the offset angle 
the string takes through the bridge pin enough to cause a significant 
difference in its length. Significant in the sense that said change in 
length in this string segment can and does have a significant effect on 
string pitch and likewise string tension.  What is problematic about 
this is that any such change in string position height to the bridge pin 
is governed by the response of the surface of the bridge to climatic 
changes, and hence quite uniform... which in turn dictates a pitch 
change that is directly related to the length of the string. Shorter 
strings will be more effected then longer strings... hence a very 
graduated and even curve of change in pitch.... which clearly does not 
happen. We see big breaks where the bridge is doglegged which need to be 
accounted for amoung other things.

Still... there is something to this that makes a good deal of sense.

RicB


    Hi Jeff,
        My intent, and I think Ron's, was that conforming to bearing
    points 
    and wood crushing was possibly/likely the cause of much of that 
    first, rapid pitch drop (after chip). I think elongation happens more 
    over time, unless one does something to speed it along (like tune 100 
    cents sharp, or vigorously work the string). And even then, 
    additional elongation will continue to take place to some extent. I 
    certainly didn't intend to imply that elongation doesn't happen.
        Like just about everything to do with pianos, there are a lot of 
    factors involved, always. Focusing on one and ignoring others is a 
    very common trap. And, of course, when writing about something we 
    tend to focus on just that one thing. We _could_ always add a 
    disclaimer "It's more complicated than that, actually" to everything 
    we say or write <G>.

    Regards,
    Fred Sturm
    University of New Mexico

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