Sudden tuning instability in Kawai KG-1D c. 1985

[Michael Magness]

On Sat, Mar 15, 2008 at 7:27 AM, Dave Smith <dsmith941 at comcast.net> wrote:

>  This is a nice Kawai grand which I have tuned since 2003.  It has a
> working DC system (dehumidifier only - this is SW FLorida).  It has been
> between 2-10c flat each year  when I arrive for yearly tuning.
>
> This year after 5 months, the owner called me for another tuning.  He
> mentioned that he hears very faint wood on wood creaking sounds sometimes at
> night from the direction of the piano.  Also, this time the piano was 10-15C
> SHARP in bass and tenor, and 10c flat in Treble.Is it likely that the
> plate is rotating slowly clockwise for some reason?  That is the only
> explanation I can think of that explains the creaking and the sudden
> instability.  What do you think?  I havent tightened the plate bolts in the
> last couple of years, since the stability was good.
>
> I did "frisk it for rodentia", as Ron N suggested when I posted the
> question about strange sounds a few months ago.  No Ro.
>
> Dave Smith
> SW FL
>

Hi Dave,

I had a similar problem with a Kawai GE-1 usually very stable, didn't vary
in pitch a great deal, tuned 3 sometimes 4 times a year. It was in a
resturaunt in a Hotel and only played by professionals, one of whom was also
a local technician.
The odd ity began about the 3rd year in March, just about this time of year.
They called and said the piano was sounding horrible. I arrived and it was
obvious that it gone sharp, then flat causing the unisons to de-tune at
varying rates. I questioned everyone about water leaks etc. but there had
been none. The next year at the same time the same thing happened, I again
questioned everyone I could find but got no definitive answer. The following
year I was again called, this time I talked to the breakfast waitress who
starts at 5AM and she said the only thing she could think of was the carpets
had been shampooed after Valentines Day like they ALWAYS were. Eureka, I had
my answer!
What I'm saying to you is do some more investigating, was the DC unplugged
for a while, was it switched to a different outlet that isn't "live" 24/7
did you have a mild heat wave causing the owner to open the windows for a
few days, or worse nights! Is the DC operating properly? Did the owner have
some construction/a leak/carpets shampooed/ small flood/etc.

-- 
The greatest challenge to any thinker is stating the problem in a way that
will allow a solution.
 - Bertrand Russell

Michael Magness
Magness Piano Service
608-786-4404
www.IFixPianos.com
email mike at ifixpianos.com
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