Thomas Cole wrote: > Trying to understand how a lossy termination results in a lower pitch, I > imagine that there is an effective elongation of the speaking length due > to the reduced rigidity of the drier wood parts in the cap and root of > the bridge, and possibly the board, and that there is an effective > shortening of the speaking length when those parts are made more rigid > by the uptake of moisture. In other words, a less stiff termination is > more likely to move with the vibration of the string and so the actual > point of termination has to be somewhere behind the bridge pin. Effectively, yea, that's it. It's been observed and noted (if not quantified to infinity) in actual trials. A flexible termination acts like a longer speaking length than a rigid termination. In a piano, this would translate into a string of given tension on the high humidity (higher compression/stiffer) board producing a higher pitch than the same string at the *same tension* on a dryer (lower compression/more flexible) board. It makes it a lot harder to come up with a simple consumer grade one sentence specific explanation of why pianos go out of tune with humidity changes, but I'm becoming more convinced that it's a real factor. Ron N
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