glass soundboard.

[Frans Sedee]

Hallo Wim,

I can tell you a little more about the glass soundboard. Mr. de Baat has so
far removed wooden soundboards from several uprights and grands and replaced
them with glass soundboards. He is reluctant tell anybody how he does it
until he has all the patents his thinks he will need which I think is
understandable. The following is just some thoughts and questions I have.
I think his experiments are made possible by modern glues that enable him to
glue glass to wood. As far as I have seen, only the soundboard has been
replaced in these instruments. The original bridges are used and the board
is glued to the wooden frame. There were no ribs applied,and I wonder if a
"crown" was made.
I assume that the piano will be a lot less sensitive to moisture changes,
and therefore will stay in tune longer. The instrument I heard was a small
upright that was not in balance in all registers. There was an increase in
sustain in the middle and low register. The frequenties absorbed by this
kind of soundboard are problably in a higher range than those of a wooden
soundboard.
(The organ doesn't have to be reinvented though.)
Glass transports vibrations at a very high speed and it does so equally
in all directions. This could increase the problems of "unclearness" of lower
voicings especially in overstrung piano's. Glass is also, if I remember
correctly, actually a liquid and I wonder how well it can support the
downbearing that is needed on the bridges. The piano I heard was also not
very loud.
I admire Kees'(short for Cornelis) energy to start these experiments. So far
he hasn't had his breakthrough and this could be because musically he hasn't
improved anything yet. I think that the glass soundboard could be a concept
for a completely new acoustical keyboard instrument, but applied in a piano
that has been develloped with a wooden soundboard, that had music written for
it with a wooden soundboard it will be difficult to define improvement.
If you have any questions for Kees de Baat I can ask them for you.
Greetings, Frans Sedee