Steingraeber factory pictures, bridge agraffes & adjustable vertical hitchpins

Ric Brekne ricbrek at broadpark.no
Wed May 3 10:49:21 MDT 2006


The answer to this question is to no small degree forced upon ones 
perspective of how the soundboard vibrates.  If one views soundboard 
vibration as more or less an independent thing from the bridge itself 
then ones answer is going to be different then if one sees them as so 
intregral as to not be seperable.  There's lots of things involved here 
to be sure.  I would suggest taking a good look at the mathmatical basis 
provided by Dr Andersen and putting as much of that to the test as is 
possible. Sure the mass charactersitics of the agraffes will have a 
profound affect.  That goes without saying.  That also (in itself) says 
zip diddly about the validity of the claims made by Stuart & Sons. 

Someone mentioned something about a presumed vertical vibrational mode 
enhancement being automatically something that would simply pump more 
string energy directly into the soundboard and actually decreasing 
sustain.  I would say that was rather premature stated.... tho I would 
be delighted to see any science that backs that idea up.  

In any case... the case at hand is simply .... does the agraffe provide 
a termination that does indeed cause the vertical vibration mode of the 
string to be reenforced and does this in turn result in a string that 
vibrates longer.  You dont strictly need a piano to test the hypothesis 
out. 

Cheers
RicB


Yoshi writes:

This was what I heard from a piano tuner in Paris who asked Mr. Paulello
about it. There may be something lost in translation, but I just assume
anything that adds stress to the board inhibits the movement of the board.
If you have no downbearing, no mass and no tension sideways, the board moves
more freely, doesn't it? (Of course that is not realistic.)


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