>Begs a question: Is this phenomenon more prominent in pianos with a long >backscale, say a big grand or clonkingly huge old upright, or with >pianos with the bridge very close to the hitch pins, say a yiddo-biddy >spinet? Regarding tuning, the string rendering through the bridge problem should tend to be a bit worse with long back scales - that's from bridge to hitch. There is more string length back there to stretch or relax, so more string length has to move across the bridge to equalize tensions. Regarding tuning stability during humidity swings, the short back scale should tend to be worse because a small bridge rise or fall makes back scale tensions change more drastically, moving more string length across the bridge and having a greater effect on front scale tensions than longer back scales would. >For that matter, what about pianos with a lot of string between tuning >pin and agraffe/vee compared to uprights with the pins nearly on top of >the pressure bar? If the string has adequate bearing and friction at the bearing points, and still renders across them controllably, there shouldn't be much difference in tuning. For tuning stability with humidity swings, again, the overall length of string affected by the bridge movement, and the proportion of lengths in front of and behind the bridge will be big factors. >There may not be much data out there, because most neglected pianos are >not big grands, in my experience, but we might think of comparisons >between small consoles and big uprights. Most of the "data" accumulated is personal observation of one isolated concern that is pretty much meaningless out of context with all the other factors that affect both the process of tuning, and the seasonal stability. That's assuming anyone even bothers to separate the two, which they usually don't. >Then again, how do you even out >other variables in the quality of the piano design (bridge design & >condition, soundboard crown stability, downbearing, wire angles around >agraffes vee bars, pressure bars, framing strength, plate design, etc? > >Alan R. Barnard Right. It all counts, and has to be taken into account. Ron N
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