Varying bridge height (was Re: Floating soundboard)

[Delwin D Fandrich]

----- Original Message -----
From: "Phillip L Ford" <fordpiano@lycos.com>
To: <pianotech@ptg.org>
Sent: March 25, 2002 10:08 PM
Subject: Varying bridge height (was Re: Floating soundboard)


> I remember seeing a piano like this in another rebuilder's shop.  I think
it was a
> Mehlin.  A fairly large chunk of soundboard had been removed (or never put
there
> in the first place).

Ah, yes. Mehlin & Son. (Sons?) Or something like that. So much for the
double name.



> The way I remember it was the area between the last rib (most
> bass-wise rib) and the rim was open.  Also the soundboard was set into the
case
> at an angle so that the bridge was quite a bit taller at the bass end than
at the
> treble end.  I seem to recall it had some sort of fanciful name like
cello-piano or
> cello-tone or some such thing.   I only saw the piano when it was destrung
and
> never got to hear or play it.

Odd. I don't remember this about the piano. It seems the soundboard was
installed in a more-or-less conventional manner.



> I think the idea of the varying bridge height is an interesting one. It
seems probable
> to me that the optimum bridge height is not the same at the top end of the
scale as
> it is at the bottom end of the scale. Setting the soundboard in the case
at an angle
> to the string plane would be a way of varying the bridge height (assuming
of
> course that you want the maximum height at one end and the minimum height
at the
> other end - which might not be the case).

And why would the 'optimum' bridge height vary from one end to the other?
Indeed, what is the 'optimum' bridge height? The added mass of the taller
bridge isn't going to make much, if any, difference. And, beyond a certain
point, neither will any added stiffness.

Del