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Richard Brekne wrote:
<p>Well, most recently Ron N's reply to a post I wrote just the other day...
and
<br>it has some merit to be sure. Let me try to explain as best my understanding
<br>allows..... Again... the string is not absolutely terminated
to begin with...
<br>energy seeps through to the other side of the termination point. And
what so
<br>?? Take an extreme example for illustration. What if you had
a "bridge pin" 5
<br>mm out from the notch ? Do you think that as much energy would zip
down the pin
<br>into the bridge compared to if the bridge pin was in the same place
as where
<br>the string contacts the wood ? What about the energy that goes beyond
the pin
<br>here ? Some of that would have to eventually hit the bridge itself
and get
<br>transferred... and some more would have to go into losses for that
short length
<br>between. The Convex bridge surface question is really sort of a variation
of
<br>the same thing. The string on a flat faced bridge is supposed to bend
(if you
<br>will) over the edge and is trapped there by the bridge pin at the same
<br>place...the idea being to provide as total a termination as is possible
at that
<br>exact point. The termination is a two component thing.. with one component
(the
<br>bridge pin) at very roughly 90 degrees from the other component (the
bridge
<br>itself) If you make the bridge convex then you more or less increase
the length
<br>of the woods component to the termination..... it takes a wider surface
on the
<br>part of the bridge to terminate the same amount of energy.... with
accompanying
<br>losses within the string for that little extra wideness. Now
whether this is a
<br>bad thing or not is not for me to say... <font color="#384CFF">I would
point out though that one of</font>
<br><font color="#384CFF">Wapins claims is that the flat faced bridge with
the angled pinning we most</font>
<br><font color="#384CFF">often see yields unnecessarily strong string
to bridge coupling, which he sees</font>
<br><font color="#384CFF">as a downside relating to sustain.</font>
<br>--------------------------------------------------------------------------------------------------------------------------------
<br>It seems to me what is stated here is being applied differently than
Wapin Co., LLP website states:
<p>"The Wapin Technology, U.S. Patent #6,100,457, is a new way to
attach a string to a bridge on a piano. For centuries piano makers
as well piano manufacturers have understood the
<br>need to provide a secure coupling for the string as it passes over
the bridge. Wapin has this same coupling but due to the unique bridge configuration,
more energy is reflected back to the
<br>string creating less of a dampening effect than the traditional arrangement."
<p>The Wapin Bridge idea is not that more INITIAL energy gets past the
bridge pin and into the bridge. The idea is that more INITIAL energy
is reflected back onto the string. The string vibrates with more
intensity. The bridge receives an increase of energy as the strings
have increased energy. It is as if a car is powered by the engine
exhaust rather than the engine. Perhaps I'm not using all the correct
terminology, but with classes I teach I have to speak in a language most
can understand.
<p>The clarification I'm trying to make is the Wapin Bridge is relying
on the string itself to increase the sustain. The bridge is a secondary
part of this. I don't pretend to be a scientist. But this is
how it has been explained to me by people I highly respect.
<p>Michael Wathen doesn't pretend to be a scientist. We have relied
on true scientists to start figuring this out. Yesterday I spent
an hour and half talking with Michael about Bob Coleman's work on Wapin.
Michael is a piano technician and has a Masters degree in mathematics.
He doesn't understand half of what Bob Coleman is studying. I don't
pretend to understand the math behind this stuff. I can believe Bob
Coleman knows what he is talking about. Have any of us designed and
implemented the audio programs he did for NASA? How many of us were
doing piano research 40 years ago with electronic equipment from NASA and
the leading piano acoustical researchers of that era? I think he
has game when it comes to studying the piano.
<p>Richard, I really like reading your posts. Don't get me
wrong. And please don't think I'm some expert. I have been
around Wapin for 5 years and have learned a few things from others.
<p>Tim Coates
<br>Wapin Co., LLP
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