[CAUT] temperature and pitch

[Ron Nossaman]

Elwood Doss wrote:
> Now Ron, we all want to know what you have to say.  Your wisdom is
> valuable to all of us.  Elucidate, sir!

It's been said so many times for so many years by so many 
people, with so many rational explanations, and it doesn't 
seem to make a bit of difference. Immediate and short term 
pitch change is temperature related. Humidity changes take 
much longer. As long as people ignore temperature effects and 
speculate that the piano went out of tune before they finished 
it because of a sudden humidity change, It's shouting down an 
empty well.

Make a decent MC gage, which will demonstrate wood's reaction 
to humidity changes rather than measuring RH% directly. Find 
yourself a practice room with a window that opens, and leave 
the MC gage in the piano for a week to acclimate. Next week, 
take some accurate pitch readings from the piano, accurate 
temperature and RH% readings, and note the reading on the MC 
gage. Close the door, open the window, open the piano. Wait 
out in the hall for ten minutes, so you won't freeze. Go back 
in and repeat your temperature, RH%, MC, and pitch readings. 
Note that the pitch has changed, as has the temperature and 
RH%, but the MC hasn't. If the pitch changed from the RH% 
change, how did it manage to do that without the MC change in 
the wood? Devise your own test, one that is intended not to 
demonstrate any one thing to prove you're "right", but rather 
to discover to whatever extent possible what is actually correct.

It never has been more difficult than this. Account for as 
many of the variables as possible, and you get more realistic 
information. Take one reading and make wild guesses at the 
rest, and you can "prove" anything. This subject will appear 
on list again in the not distant future, starting, once more, 
at the beginning.
Ron N
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