Article about bridge agraffes - function, types

[Ron Overs]

Ric,

>One of the advantages or spin-offs of the 'floating soundboard' is 
>the rock like stability of tuning.  I look after a couple of Stuarts 
>and the tuning stability is to die for.  Even after the flight from 
>Australia, 3 days at the airport and the road journey 
>to its destination, the concert grand tuning was solid and at pitch. 
>I literally could not even find a unison to tidy up.

Similarly, pianos with once-crowned soundboards will exhibit tuning 
stability to 'die for' once the soundboard becomes totally flat and 
the downbearing disappears, but they will also acquire a few other 
tonal characteristics, along with the improved tuning stability, 
about which we may not be so delighted.

>  But why do you need downbearing when, with agraffes, you can have a 
>thinner soundboard with ribs which only act to disperse vibrations. 
>If you think about it, the traditional crowned soundboard 
>construction is the eventual kiss of death to the piano.

Indeed, the kiss of death will come to all of them in good time. But 
do we want it to be evident before the piano is crated, or not long 
after it arrives at the showroom, or five years after the ink dries 
on the cheque, or are we looking for a longevity of tonal 
characteristics which might endure for perhaps thirty years or more?

I just don't happen to share Wayne Stuart's philosophy that a good 
tone can be produced without a stiffened diaphragm assembly being 
balanced against a downbearing force from the string set. Certainly 
it is possible to produce the upper frequency harmonics with little 
or no downbearing, but the fundamental frequencies, which require a 
much bigger amplitude to produce a satisfactory sound-pressure-level, 
would seem to be dependent upon some level of downbearing being 
resisted by the soundboard assembly.

That's just how it appears to me at this time.

Ron O.
-- 
OVERS PIANOS - SYDNEY
    Grand Piano Manufacturers
_______________________

Web http://overspianos.com.au
mailto:ron at overspianos.com.au
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