>Once again, your response shows that you do not understand at all, >since there has been no discussion in this thread of compression >waves in the soundboard and the strings. What is under discussion is >the waves that pass through the bridge. No, what is under discussion is what moves the bridge and soundboard. >You talk of "my" theory as though I had dreamed it up out of thin air >without any scientific evidence and as if I were claiming some >novelty. Then who's theory is it if not yours? >On the contrary I have challenged you (in a part of my >message you have avoided reproducing) to produce one serious URL, >such as a University site, in support of what you are claiming. Oh, sorry. Since you only asked that once in passing, I mistook it for just another diversion and didn't give it much weight. As far as I know, there isn't one. You see, the strings moving the bridge is my own theory, dreamed up by me, based on sound mechanical and physics principles, so it isn't likely to be on a university web site anywhere. Oddly enough though, two piano designers, builders, and fellow rebuilders who have against all apparent odds actually given it some thought, seem to hold similar views. Imagine such a thing! Two different people who have spent years studying how pianos work and building pianos, reaching conclusions similar to my own. Perhaps we should post our collective theory on a web site so we too could be quoted as undisputed authorities. Better yet, with three different sites showing animations, with circles and arrows and lots of mathematical formulas, mine (and at least two other folks who have given it some thought) would undoubtedly become the theory of choice. By the way, I assume you have at least one URL illustrating how piano soundboards are moved by vibrations through the bridge rather than by the strings moving the bridge. I'm sorry, but I must have overlooked it when you posted it in support of the anonymously conceived theory you are espousing. I'm not interested in general vibration theory stuff mind you, any more than you are interested in simple mechanics, just the list of sites dealing with this particular subject. >You >ask "how small a bridge movement constitutes no movement at all" and >the question is perfect nonsense. If there is some movement then >there can't be no movement, but what is supposed to be the context of >this meaningless question? You are claiming that the string bodily >moves the bridge in such a way as to induce the soundboard to emit >the sound appropriate to the string's vibrations and I say that it is >impossible for this to happen. Yes, I know what I said, and I know what you said. What you just said is the context of my far from meaningless question. So I take as your answer that any measurable movement of the bridge by the movement of a string is impossible by your theory. That is not a question. >No one is claiming that there is no disturbance or stress at the >meeting of the string with the bridge, otherwise no sound would be >transmitted, but to claim that this disturbance results in the bodily >movement of the bridge and drives the soundboard as a solenoid drives >a loudspeaker is nonsense. That disturbance results in the >_vibration_ of the bridge, which is the movement of a compression >wave through the bridge during which every molecule of the bridge >will be set in an oscillatory motion about its position of >equilibrium. These vibrations will travel through the bridge in the >same way whether or not the sum of the additional forces exerted by >the vibrating strings on the bridge, whether laterally or vertically, >amounts to zero as in an example I gave earlier in the thread. I've read this explanation plenty of times, and hard as it seems for you to accept, I understand your theory. I just don't agree with it. Ron N
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