Buzzing soundboard

[Avery Todd]

Ed,

   Have you checked the gluing of the ribs to the soundboard? Any cracks
in the board that might be running across a rib? That'll sometimes buzz.
   How about the gluing of the board around the rim? The "pressing on the
board" thing you mentioned sure sounds like a loose glue joint somewhere
in the board, ribs, rim/case area.
   Let us know if you find it.

Avery

>All right my friendly wizards:
>
>th piano is a Chickering Grand, about 4'7" I think.  Piano Atlas has it
>manufactured in 1908.  It was Rebuilt in 1995.  Guy did a nice job on most
>of it, but some problems with which I have been dealing for the past 3 years.
>
>There was a bit of a buzz on some notes, especially Bb5 and A5, also Bb 4.
>We haven't been able to eliminate it.  I investigated all rattly things,
>but no much help.  The client discovered that pressing on the sound board
>behind the upper treble caused it to diminish.
>
>There is a round nut that goes through the soundboard that has two small
>holes for tightening.  It is under the F#5, G5 strings, between the bridge
>and the string termination.  I had to loosen the strings to get at it, but
>it was loose, so I tightened it.  No improvement.  There is another nut
>just like it under the A1 strings in the bass, and the lower treble strings
>that cross under the A1 strings.  I didn't try to tighten that nut, but it
>might also be loose.
>
>The buzz is worse than it was the last time I worked on the piano, and is
>really unacceptable.  Pressing on the soundboard does almost eliminate it.
>
>When the rebuild was done, the bridge structure was not replaced exactly.
>Pretty close, but the E5 treble string actually touches the plate.  I don't
>know if this is part of the problem.  It didn't seem to make a difference
>when I loosened this string, or put felt between the string and the plate,
>so I took it out again.
>
>Any ideas as to where to go from here???
>
>
>Ed Carwithen
>John Day, OR