Sound waves(The behavior of soundboards)

[John Delacour]

At 12:42 AM -0500 12/19/01, Greg Newell wrote:
>John, you have determined that there are 2 distinctly different 
>sounds derived from striking the top or the side of a bridge. Can 
>this be duplicated outside the piano? Is this done in some way while 
>the piano is still strung?

The difference is vivid whether or not the piano is strung.  I 
originallly tried it on an unstrung Steinway grand.  I have just 
tried it on a strung upright.

>Can this be repeated with a piece of maple (or other bridge material 
>... ?????)

I have only a 4ft piece of 2 x 1 maple to hand with the wide face 
tangential to the annual rings.  There is a very slight difference in 
the timbre which I would put down to the difference in stiffness etc. 
of the two planes.  If the maple were 1" square with the rings 
running diagonally, I'd expect the sound to be the same.

JD