Wim, If you didn't understand what I was saying, I feel sure there are others who didn't as well. I'll try again. You say you can't believe that the pitch of the speaking length can be changed as much as 50 to 100 cents before the string will move at the bridge. Well, I can, because that's what I measured. It will depend upon how much of a "set" the string has taken at the bridge. I would expect it to be more in some cases, and less in others. I'll admit I did not take many measurements. I plan to make more measurements in the future, and I expect to find a very wide range of values, for the very reason I just mentioned. No, Wim, I am NOT saying playing the note softly will equalize the tension across the bridge. You know that. I said pounding will cause it to move if it is about ready to move anyway. If the tension is not equalized across the bridge, but the string is about ready to move, but you play softly, nothing will happen. But if you do pound, or if the pianist pounds, then it will move, and the pitch of the speaking length will change. Now consider the fact that you have a whole bunch of strings whose tensions are only partially equalized across the bridge, because there is no way you can completely equalize it. All it takes is for the relative humidity to change, the bridge to swell or shrink, or the temperature to change so that the difference in expansion coefficient between wood and steel will cause the string to slip a microscopic amount at the bridge, or someone to pound the key; the string will move at the bridge, and your perfect unison tuning will be spoiled. I think this makes lots of sense. Sincerely, Jim Ellis
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