Gerald Groot wrote: > OK, a little play in words....... In so many sentences you and others are > indeed saying that it is not the main reason. I am saying that I think it > is. Has the rise and fall ever been measured? You mean instead of just taking it on faith? Have you ever calculated the string elongation change necessary to produce the tension change to take a string's pitch 5¢ higher or lower, and how much the soundboard would have to rise or fall to accomplish this at the low to vanishing downbearing angles we find in pianos? How about comparing downbearing readings before and after seasonal pitch swings? If the soundboard's moving enough to make the tensions change that much, the angles will change too. > Doors and door jams expand and contract as much as 1/4" during each seasonal > change. Sound boards do expand and contract a lot. If it is not the > expansion and contraction of the sounding board causing it, then, what is? Read what has already been written in this thread, and chase it down in the archives. There's plenty of discussion. Ron N
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