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

[Dave Smith]

Thanks Michael, I did grill the owner about any humidity adding events.  Says no.  So I really suspect the piano itself.  Any more suggestions welcome.  Thx\

Dave Smith SW FL
  ----- Original Message ----- 
  From: Michael Magness 
  To: Pianotech List 
  Sent: Saturday, March 15, 2008 10:09 AM
  Subject: Re: Sudden tuning instability in Kawai KG-1D c. 1985





  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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