Philip Jamison wrote: "How much does a robust A440 tuning fork vary in pitch with temperature?" See answer below. I would ask: How much does a robust piano vary in pitch with temperature? More than the fork, from what has been reported on this list. I've read you should place the fork on the piano's plate while you get your other tools ready. The piano and fork will be at the same temperature. If that happens to be 95 degrees or 55 degrees, both will be "off" in the same direction. The question is, how much different? I have a very common blued steel John Walker fork which I calibrated to A440 at 75 degrees F. When placed under my arm for a few minutes (85 degrees? 90?) it reads 1.39 cents flat. After 5 minutes in the kitchen fridge (35 degrees?) it was 2.87 cents sharp. Five minutes on a table (75 degrees), it still felt cold on my neck, but was just about back at 440, only 0.14 cents sharp. I also have a slightly shorter, slightly stockier chrome plated steel fork with a round ball on the handle which is labled only "Germany" and "440". I don't remember where it came from. It is also set at 440 at 75 degrees, but the "armpit-ch" on this one is 1.52 cents flat. Five minutes in the fridge, it was 1.58 cents sharp. Know thy fork. Now, if I could just learn how to use the darned things to actually tune a piano, I'd pass the last of my RPT exams! (as long as I don't have to tune in a refrigerator or in August) Greg Graham Brodheadsville, PA __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com
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