List: In the October 1998 PTG Journal, page 21 is an article on this very subject by Jim Ellis. dave Conrad Hoffsommer wrote: > 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. -- _______________________________________________ David M. Porritt, RPT Meadows School of the Arts Southern Methodist University Dallas, Texas mailto:dporritt@swbell.net _______________________________________________
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