Variation of temperature

[S. Brady]

On Sun, 12 May 1996, Michel Lachance wrote:

> I am looking for precise datas about pitch drift caused by a temperature
> change.  For example, how much cents does the pitch increase if the
> temperature drops by five degrees?  (which could easily happens when you turn
> on the air conditionning)

      Michel,
      According to Jim Ellis's article in the May, 1995 Journal, p.
35-6:
"A rapid drop of four degrees in ambient temperature can cause the piano,
especially the middle section, to go sharp by about 5.5 cents. A similar
rapid rise in temperature can cause it to go flat by the same amount. This
is a transitory effect, and it goes away if the piano is left alone long
enough for the strings and plate to come to the same temperature."



Steve Brady, RPT        "Chaos is the law of nature; order is the
University of Washington      dream of man."    --Henry Adams
sbrady@u.washington.edu