Seasonal pitch change:

[RicB]

Ron, and others.

I have written several previous posts these past two years on this 
subject. Indeed the previous thread just a couple weeks back refered 
this thinking back your way. I suppose I should take it back further and 
credit Newton, as he was the first who brought my attention to it. Who 
and what stimulated his thinking way back when I dont know. Since Newton 
however, I've run into several folks around the globe who have been 
skeptical about the rise and fall of the soundboard idea.  All these 
inputs eventually got me to thinking about looking at it from a 
consequences view point.  I contacted a couple math folks I know, Sarah, 
Mark Davidsen, and my friend Alex Galembo for thoughts on using basic 
geometry to show changes in tension for changes in deflection.  Youngs 
modulus had to be considered, but beyond that it was pretty basic to 
show the kinds of basics I wanted to show.  And I have a good deal of 
off list correspondance with several other knowledgeble folks on this 
and several other matters. As you say, up to this point this particular 
subject has has not seen much in the way of concrete work done on it.  A 
simple math model simply strengthens the thinking on this line so far. 
It's hardly a conclusive study had has nothing to do with miracles. It 
does show people are thinking, and physical measurements are no doubt on 
the way, by more then just myself as well.

About the slanted pins thing...  I'm not sure at this point I buy it. 
But I havent thought it through much yet.  I would point out though that 
you evoke the concept of strings being moved up and down the bridge pins 
by the surface of the bridge.  Seems rather at odds with previous 
statements I've heard from you on the string seating theme.  That said I 
dont see this affecting the speaking length (sideways I suppose you 
mean) enough do account for more then very marginal affects in long 
strings. An increased offset angle between the two bridge pins might 
contribute some, but like I say I havent thought  bridge pin caused 
lateral change through much yet.

Ric B


    Ron N wrote:

    Since the role in soundboard rise and fall has apparently
    suddenly and miraculously been discovered to be relatively
    inconsequential to the process, I expect that shortly after
    the flurry of rim and plate movement, rotating pin block,
    rolling bridge, and warping continent theories dies down for
    lack of rational connection, the observation that string path
    length changes with strings being moved up and down bridge
    pins slanted in apposing directions by humidity induced cap
    dimensional changes will be equally suddenly and miraculously
    discovered as being a likely candidate, to the edification of
    - some, maybe. That is, if anyone actually runs some physical
    tests and thinks about it.

    Hey, it could happen someday.
    Ron N