> And, yes, it was just my suppostition. But something has to explain the > source of change in old pianos that have had all the time necessary for the > soundboard to collapse, strings to stretch, etc., as much as they possibly > could. But still fall flatter if left alone for long stretches. If you are going to limit the possibilities to just string stretching, soundboard crown dropping, and tuning pins turning, you'll have to take what you can get. If you include the compressibility and structural deterioration of the wood in the bridge cap and pinblock, allowing the pins to migrate, you have more things to chose from. I can well expect the California folks to report no significant pitch drop over the years, but they don't experience real seasons there. In states that aren't climate controlled, wooden parts, in which are embedded metal parts under significant continuous side forces, take tremendous cyclic pressure abuse from humidity swings. Now break out the string scaling formulae, and determine pitch changes from diminishing side bearing angles across bridges, and length shortening from the tuning pins migrating in the block, and you'll find that the pin doesn't have to turn in the block at all to produce a big pitch drop over time. It's obviously a moot point though. If the techs won't believe it, the customer surely won't. Just tell them the tuning frequency is too low and duck out the back while they're chewing on the pun. Ron N
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