no down-bearing revisited

[David Skolnik]

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Michael,
You don't need a flame suit, yet, but list protocol, as I perceive it, 
would have you ask yourself at least two questions  ......first, whether 
you are significantly redirecting or diluting the focus of a particular 
thread (group of posts under the same title), and second, make an attempt 
to read and understand the previous postings, both in the particular thread 
and, to some extent, in the archives, though I admit, the archives can be 
daunting.  As the perpetrator of this current mini-thread, and as one who 
struggles, at times  to articulate ideas clearly, I feel a bit of that 
Mother Bear & Cubs instinct.  I'm trying to have some specific questions 
addressed.   I suspect and fear that consideration of downbearing in 
harpsichords, while related, will digress into a harpsichord 
discussion.  If you wish to pursue that idea, give it a different title. 
With regard to your question as to whether NO downbearing would make a 
difference, you should note that, apart from any other point I was 
attempting to make, John Hartman discussed downbearing's function in 
enhancing the impedance of the soundboard which resists the premature 
depletion of vibrational energy of the string.  The difference between NO 
downbearing and NEGATIVE  downbearing on a piano is conceptual and a 
function of bridge pins.  Without bridge pins, there is no such thing as 
negative downbearing. In that case, downbearing would move from positive to 
NONE with the exception of that "event horizon"- like envelope where the 
downbearing force was so minimal as to allow the string to buzz against the 
bridge surface when energized.  After that, there would be virtual 
silence.  Bridge pin induced NEGATIVE downbearing is, of course, actually 
POSITIVE UP-PULLING!!. The vibrational energy from the string is conveyed 
to bridge and board by the bridge pins, but the forces at the string / 
bridge interface are different.  There is, I suspect, no impedance-inducing 
stiffening of the board taking place, and the tendency of the string to 
move up the pin towards a neutral position would be constant and 
de-stabilizing.  To be sure, if there is, as I suspect, a salutary function 
of what the Wapin Bridge patent refers to as the "bearing point edge", that 
function too would be compromised in a POSITIVE UP-PULLING 
configuration.   Any of that clear?

David Skolnik RPT



At 10:46 AM 2/1/2004 +0000, you wrote:
>Hello List et al
>I'll just repeat something I put on the list some time ago. I regularly 
>tune a Harpsichord with NEGATIVE downbearing. Only the opposing angles of 
>the bridge pins keeping the strings in contact with the bridge. I used 
>regularly to find the strings floating above the bridge until I determined 
>the reason and simply pulled the pins out a little. But note, my friends, 
>this negative down-bearing made no discernible difference to the quality 
>of the sound. But that's a Harpsichord. Any reason for thinking that NO 
>downbearing ( note "NO" not "NEGATIVE" ) would make all that difference in 
>a piano?
>I have no flame suit
>I'm just geared up in a space suit ready for that promised trip to Mars.
>Regards from a beautifully clear-blue sky'd Sussex Downland Village. Yeee  Ha!
>Michael G (UK)

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