Odd partial

David Porritt dporritt@post.cis.smu.edu
Thu, 31 Oct 1996 06:26:00 -0600 (CST)


List:

Our newest Steinway "D" (3.5 years old) has always had a strong beat at
the 10th partial on G-2.  When the unison is otherwise as solid as it can
be there is a +/- 2 beat per second at the 10th partial.  It's always
been there and fortunately pianists have never complained.

Yesterday I had a couple of extra minutes so I measured some partials.
On one string the 10th partial was 4.6 cents flatter than the other two
strings.  This is a 21-ga. unwrapped string.  I measured the 8th partial
and they were quite close on all three strings.  Matching the 10th
partial using a SAT makes quite a bad unison.  Matching the 8th (or any
others) makes a good unison.

What would make one string have one flat partial?  More inportantly, what
is the fix?  I thought about putting on a new string but unless I have
pretty good evidence that this is the fix, I don't want to thread that
under the bass strings and fight the tuning of it for a couple of weeks
and not have it help.

Suggestions?????????????

dave

_______________________________________________

David M. Porritt, RPT
Meadows School of the Arts
Southern Methodist University
Dallas, Texas
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