Hi Terry, You are missing the point--the thread is about pitch drop over time, so this data is from my point of view is a perfect example of what happens over 160 months. At 06:15 AM 5/13/2005 -0400, you wrote: >I agree it would be interesting, but start with a decent STABLE AT PITCH >(A440) piano - not a piano that you just did a 92-cent pitch raise on. > >Terry Farrell > >> 1992 01 pitch corrected 92 cents at A4 humidity 40% (including overpull) >> 1992 02 floated pitch at 7.5 cents sharp at A4 humidity 47% >> >> Today? Pitch correction at A4 of 31.6 cents and worst note of 120 cents >> humidity 29% (including over pull). >> >> Total pitch change over 160 months at A4 = 39.1 cents >> >> My "guestimate" is that for every 5% humidity change A4 drifts 4 cents. >> This would give around 14 cents of the pitch change for the humidity >> portion. >> >> Plugging that value in makes the pitch correction at A4 more like 25 cents >> in a mere 160 months between tunings, or about 0.15 of one cent per month. >> >> I have no way to factor in humidity change for the worst note but if we >> ignore it then 120/160 =~ 0.75 cents per month. >> >> I hope more folks will do this sort of analysis and post it to the list--I >> found Conrad's data *most* interesting! Particularly that the piano was at >> 436.7 on 01/03 and a year later was 436.7 again. Too bad there was no >> measurement of room humidity to go with this! > > >_______________________________________________ >pianotech list info: https://www.moypiano.com/resources/#archives > > >-- >No virus found in this incoming message. >Checked by AVG Anti-Virus. >Version: 7.0.308 / Virus Database: 266.11.9 - Release Date: 5/12/2005 > > Regards, Don Rose, B.Mus., A.M.U.S., A.MUS., R.P.T. Non calor sed umor est qui nobis incommodat mailto:pianotuna@yahoo.com http://us.geocities.com/drpt1948/ 3004 Grant Rd. REGINA, SK, S4S 5G7 306-352-3620 or 1-888-29t-uner
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