At 23:59 11/30/98 EST, you wrote: > >It is common knowledge that the pitch of a pipe organ varies with room >temperature, but just how much? > >Occasionally I will be asked to tune a church piano with the pipe organ when >the sanctuary is much cooler than it will be on performance day. I check the >organ and it is off pitch. The question is, is there some formula that will >tell me where the organ pitch will be at normal room temperature. In other >words, if the room will be 10 degrees warmer when the piano and organ will be >played together, how much will the pitch change? > >Dave Bunch From: "The Art of Organ-Building" George Ashdown Audsley - 1906, Dover reprint 1965 Vol II, p. 637: Chart- "Vibration-numbers according to diapason normal at different temperatures" 59F - 435.0 60 - 435.4 61 - 435.9 62 - 436.3 63 - 436.7 64 - 437.2 65 - 437.6 66 - 438.0 67 - 438.5 68 - 439.0 A fancy numeric formula didn't jump out at me, but may be deduced from the text when my eyes open fully, but from that short list it looks almost like 4/9Hz per degree F. Conrad Conrad Hoffsommer mailto:hoffsoco@luther.edu Luther College (319)-387-1204 Decorah, Iowa 52101-1045 The best things in life aren't things.
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