Article about bridge agraffes - function, types

[Ron Nossaman]

>> Keep in mind that the wood isn't the termination in a standard 
>> bridge configuration. The pin is, and as long as the pin is 
>> solidly embedded in the wood at the cap surface, It is very 
>> nearly as efficient a termination as an agraffe. That's why 
>> some of us have gone to laminated bridge caps.
> 
> Yes and no. I think that as long as the string touches the wood cap because
> of downbearing, it will influence the sound of the string too, and is likely
> to diminish the efficiency of the termination as a whole (more or less,
> depending on how stiff that wood cap is). 

Hi Calin,
The hardness of the cap determines the solidity of support of 
the pin (termination), not the damping of the string directly. 
That's why CAing the pins clears up a lot of termination 
problems. The CA isn't put under the string in the middle of 
the cap, it's soaked in around the pin.


> Interesting. I can't tell how much of the improved sustain is because of the
> added mass and how much because of the improved termination quality of the
> agraffe.

Exactly! And since the sustain can be so dramatically 
increased with mass loading in a standard bridge configuration 
(given a decent bridge cap and pinning, naturally), the 
responsibility of the improved agraffe termination for 
increased sustain comes into reasonable doubt.


>> I expect that most of us doing design modifications with 
>> rebuild have at least one bridge agraffe design we're looking 
>> for an excuse to throw enough cash at to try out in a real piano.
> 
> So what would yours look like?

Why not? Somewhat like this - (drawing). Designed for minimum 
loss of bridge height to accommodate installation. This could 
be either extruded and milled, powdered metal cast, or stamped 
and formed from sheet.

If you see a patented version in a piano next year, remember 
where you saw it first.
Ron N
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