Tuning instability question

[Pianocraft@aol.com]

In a message dated 96-02-06 09:46:56 EST, you write:

>What I have not been able to determine is when we have 50% in the
>Winter and 50% in Spring or Summer the pitch will actually be alittle
>sharper than A-440.  That doesn't make much sense to me, because I thought
>50%  humidity would be the same, but I have to pull the pitch down to keep
>it at 440 in the Summer. However, the temperature is higher in the Summer,
>going up to 72* but in the Winter we average around 68*.  Maybe that is a
>factor.  Any comments.

Temperature affects the speed of moisture exchange from air to wood. Higher
temp equals faster exchange.

John Hartman