This Needs A Definitive Settlement was RE: 12 cents

[Thomas Cole]

I'm not aware of any science other than what Dr. Sanderson has done, but 
I remember hearing about a demonstration of string settling that was 
performed at Tuners Supply, Sunnyvale, CA some years back (by one of the 
early California settlers ;-).

An old upright was pitch raised to 440, after which the back of the 
soundboard was pounded vigorously with a rubber mallet, along the line 
of the long bridge, and it was later found that the tuning had slipped 
significantly.

I'm not suggesting this as a method of doing single-visit pitch raises 
as it probably wouldn't go over well with most owners - this was only a 
demonstration, after all, and it tends to verify what Ron N. posted 
about friction across the bridge.

Another thought is that if a tuner were to delay the second tuning for a 
couple of weeks, it might not help matters much of the piano were not 
played during that interval. If the pitch raise is not challenged by 
pounding or significant weather changes, I would doubt that a majority 
of the strings are going to ooze through the bridge pins on their own. 
So it may be a judgment call whether it's better to come back for the 
fine tuning.

An interesting experiment, which might even work in the field, would be 
to apply some kind of vibration to the soundboard after a pitch raise. 
You could warn the customer about the unusual noise it would produce, 
and it wouldn't look like you were trying to destroy the instrument.

Tom Cole

Alan wrote:

>Don wrote: "...if you pitch correct a piano ... and then tune it ... you
>may find that you wish you had waited to do the fine tuning. Piano
>frames shift. Sometimes this shift is very dramatic at the bass break or
>other areas."
>
>I may be wrong (always a distinct possibility) but didn't Dr. Sanderson
>and others test this whole business and determine that all changes to
>the piano caused by changing string tensions are immediate?
>
>I'd have to go back and look, but I'm pretty certain that Randy Potter
>has cited this information and stated, in effect, that the time-honored
>belief that pianos needed to "settle" following a pitch correction was
>not correct.
>
>As this issue has a definite impact on the way we conduct business, I'd
>like to see a definitive answer here, not just opinions or anecdotal
>experiences.
>
>Anything, anyone?
>
>Alan Barnard
>Salem, MO
>
>---
>Outgoing mail is certified Virus Free.
>Checked by AVG anti-virus system (http://www.grisoft.com).
>Version: 6.0.489 / Virus Database: 288 - Release Date: 6/10/2003
> 
>
>_______________________________________________
>pianotech list info: https://www.moypiano.com/resources/#archives
>
>
>  
>