Hi Rich A Interesting mention of Helmholtz and physical pitch of C 256. The conclusion I am drawing is that 256 is 2^8. At A440 C is 261.63. Hmmm I wonder what it was at A435? And then that doesn't mean much because if organs were traditionally tuned in Meantone centered on C then A would be a hair above a Major 6th (5/3) up.(426.6 from 256) Somewhere I heard or read that the reason A 435 got changed to A440 was that A440 was close to an ET Sixth above C in ET instead of a nearly pure Sixth above which it would have been in Meantone. But back to 256 pitch. Doesn't a 4 foot pipe give close to C 256 because of the speed of sound at 70 degrees F ? It looks like it would take a 4.4 foot pipe to give 256 at 70 degrees. At some temperature a 4 foot pipe will give 256. FWIW ---ric > There is a good history of how the A=440 came to be, Helmholtz, > physical pitch,C=256, etc. > > Fun stuff.... > > Draw your own conclusions... > > Rich A. >
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