> > Ron: > > > > Certainly the dimensional changes you suggest would create a pitch > > difference, but what about the not so inconsequential friction > systems > > of the front scale: bearing cloth, counterbearing bar, agraffe or > capo, > > etc. > > The friction levels of the front scale are usually just that - > relatively inconsequential compared to that at the bridge. > > They're inconsequential compared with lots of things which doesn't make > them per se inconsequential when it comes to the string "rendering" past > them; the friction exists and is eminently measurable. My question > stands. Could the "couple of thousandths" move sufficiently and in such > "even" patterns past those friction points and create the various and > varied effects we find in piano pitch change? I didn't say they were inconsequential at the capo, just relatively so compared to the bridge friction levels, and don't claim to be able to provide infinite details describing the cause and effect of every pitch anomaly we find in pianos. If your question refers to pinblock movement of a couple of thousandths make a difference, past the counterbearing friction points, to the tuning, I'd say yes it can and does. Always? Obviously not or we wouldn't get those strings that ping when you bump them down. To what degree depends on other details. Is it the ONLY, or even the PRIMARY cause of pianos going out of tune, no, I don't think so. The one think I'm sure is NOT the primary cause is soundboard rise and fall, as we were all taught. We do have soundboard rise and fall, which will make some difference. We do have bridge movement fore and aft, through soundboard distortion and bridge length changes which cause speaking length changes that will make some difference. We have bridge caps shrinking and swelling, changing string lengths by both changing bearing and moving strings up and down slanted bridge pins, which will make a difference. We have pinblocks experiencing dimensional changes which change string lengths and will make a difference. We also have a number of friction points that will help to disguise what we think we see happening, which will make a difference. We have different lengths of wire outside the speaking lengths of every single string, which will make a difference. We then have every warping, twisting, bending, and rotating scenario anyone can dream up whether there's any plausibility to it or not, that might possibly make a difference. Then throw in thermal effects, individual tuning styles, and more than a little Voodoo, and the piano's out of tune again. > I'd love to hear Jim Ellis chime in on this. > > > > Paul > > Then you'd better cross post to Caut. He doesn't read Pianotech. > > My sentiment was out of respect for Jim, Ron. And mine wasn't out of disrespect, Paul, it was factual and informative. The fact is that he doesn't read Pianotech, and if you are sincere in wanting to have his opinions on this it would seem the sensible thing to do would be to make him aware of it. Ron N
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