>Hi Ron, > >Scared is the word! How did you derive those numbers? > >If I understand rightly, an 8 cent change on an S&S D, from >440 to 442, would translate to a tension change of about 400 >pounds? I would have thought more considering how obnoxious >they are about that. Interesting! > > Newton Yep, I just checked one I've got on file at 46,849@440, goes up to 47,276@442. I don't know how much of that touchiness with pitch changes is plate flexibility, and how much is the soundboard. I'm always struck by how flexible the plate is in these pianos, but I haven't put one of my boards in one yet to get a stability comparison from the board. This tension at pitch question came up enough, and I was curious enough too, that I set my spreadsheet up to compute the note frequency from a user defined A-4, and figure the tensions from that derived frequency. All I have to do at this point is change the pitch of A-4, and read the updated total tension. Most of the time, it's not of any real use, but it's been informative and educational enough times to have been worth the trouble. Ron N
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