Hi, Ric: << I am not sure what the numbers mean. do you have tension in pounds and string length in millimeters? So it looks like 97 lbs for note #85. That seems off by 60 lbs since most top notes are around 150 lbs, 170 at the most. --ric >> That's right (the legend is at the bottom of the page). I am absorbing Juan Mas Cabre's article in the PTG 7/2000, pp. 56-65. I confess I had not read this article until tonight, but Clark Caccola refers to it in his earlier post. This author states that the wire used for pianos in the middle through later part of the 19th century has much different properties than modern hardened steel wire. The wire has lower breaking strength, is more elastic and has a lower inharmonicity with more fundamental to the sound. He also points out that if the pianos were originally tuned higher, than the wire size in the upper notes should be smaller when tuned at A440. (p. 63) He recommends his "Pure Sound" wire for pianos from the middle 19th century because it is more similar to the wire of the period. His article includes formulas to calculate string tension based on the type of piano wire, using "a simplified form derived from the Taylor formula:" He multiplies these four factors: the square of the frequency in Hertz, the speaking length in meters and the diameter in meters, and 24662 (for modern wire, or 24819 for his Pure Sound wire, or 24407 for Malcolm Rose wire). He recommends using these formulas to establish the type of wire used on any given period piano. (p. 62) I guess I have some work to do. Bill Shull
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