CAUT Guidelines, humidity

[Fred Sturm]

I agree wholeheartedly with Jeff's point. In terms of keeping pianos in
even bearable tune, not to mention adequate, or, dare I say, optimum
tune, humidity swings are what cause me to use up the most hours. 
	How to quantify for purposes of the guidelines? As a starting point, we
might suggest some arbitrary standards for excellent, good, fair and
poor conditions. Cent swings for those categories might be,
respectively, 5, 10, 15, 25 (average cents off A440 for the average
piano, where the performance piano(s) might be kept within 2 cents,
piano faculty within 5, down to uprights in practice rooms within 25, to
name some arbitrary figures). 
	Then we need to know the percentage humidity swing that produces the
cents swing. At my institution, a 50% rise over the summer (from circa
20% to 70%) creates a rise in average pitch of more or less 25-45 cents
(that variation within the average piano, depending on where in the
range one is measuring).
	Now how many tunings per piano are necessary to keep them within the
standard cent deviation? This will not be an exact science, but might be
a good starting point to get a handle on this factor. I know from
experience that the few pianos I service in humidity controlled
situations are remarkably stable. Can't imagine what life would be like
at the university under those circumstances. 

	I'd also like to offer that piano loan programs should be addressed
from the point of view of how much work they create. In my experience
(with Baldwins), I need to tune these pianos 50 to 75% more, and service
needs are high - every screw in every piano must be tightened, damper
troubleshooting, alignment of parts, etc., etc. It would be good to have
some statement to the effect that new loaner pianos will require more
hours per piano, preferably with a multiplcation factor.

Regards,
Fred Sturm
University of New Mexico

Jeff Tanner wrote:
> 
> 
> But one thing I was curious about.  How were the values derived which are
> assigned to the climate control variable in the formula?  I look at the
> first variable, "Condition", and see that a piano in poor condition can be
> given a factor of .25, and one in fair condition gets .50 (this is a
> useable instrument).  But the most weight that can be assigned to a
> building with poor climate control only affects the equation by a value of
> .70.  I fully realize that these were not arbitrary figures and that much
> study went into their creation.  But some things have changed in regards to
> institutional climate control since the formula was first adopted and I
> wonder if this variable needs to be addressed.
.......
> 
> Does a factor of .70 adequately address these changes which weren't so
> drastic prior to these new HVAC systems?  Isn't a piano, regardless of
> condition, but which can't be kept in tune about as useful as one in "fair"
> (or worse) condition?  A piano in fair condition can at least be tuned and
> used for ear training and even rehearsal (when I was in college, fair to
> poor was the norm for about half of the general practice rooms -- fair to
> good pianos were reserved for piano majors only -- there was no "excellent"
> for a number of years). 
> 
> Jeff Tanner, Piano Technician
> School of Music
> University of South Carolina
> Columbia, SC 29208
> (803)-777-4392 (phone)
> (803)-777-6508 (fax)