Greetings, I wrote: I would think that it is the board rather than the plate. When a string breaks in the treble, the adjacent strings of that note seem to always go sharp, and when the string is replace, they come right back down. Would one string missing allow the plate to relax?, and if so, only on the immediate area? David replies: << I don't know. One string breaking takes over 300 lbs off the plate whereas it takes only a small percentage as a function of a change in the deflection angle off the soundboard. David Love >> And Ron writes: >>Would one string missing allow the soundboard to rise, and if so, only in the immediate area? Got any idea how length change in a string affects pitch, and how much soundboard rise it takes at the existing bearing angles to produce the length change necessary to affect the pitch difference observed?<< What I wonder is why such a localized effect of losing a string? Cast iron is pretty stiff, and if losing a string allows the plate to relax, wouldn't it affect more than just the two notes on either side? I have measured soundboard drop under tension, and it isn't uncommon to see them drop .050" when the piano is chipped to pitch. Some more (such as the Chickerings with the inner rim), some less (Steinways and Baldwins), but there is still a lot of movement up and down. Regards, Ed Foote RPT http://www.uk-piano.org/edfoote/index.html www.uk-piano.org/edfoote/well_tempered_piano.html
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