Wapin (Re: String vibrations)

Phillip Ford fordpiano@earthlink.net
Sun, 21 Sep 2003 13:28:49 -0700


>  I dont know Phil, but it seems fairly intuitive that a pulse, or wave... or
>however you want to conceptualize it... traveling down a wire and hitting an
>end point is going to tend to get deflected by the condition of that endpoint.
>If its angled as the bridge pins are, it would seem reasonable to assume that
>there will be some degree of force exerted on the vibrating string on that
>angle.. How much is another matter altogether... but its rather hard to
>disregard the data Wapin has assembled on the subject.

Perhaps your intuition works differently from mine.  Maybe one of us 
was a woman in a past life <G>.  It seems to me that the string is 
locked down by the bridge pin, regardless of its angle, and that 
what's happening is more a matter of the stiffness of the termination 
than the angle of the pin.  If you read the excerpt from the Wapin 
patent that I included in the previous post they seem to believe that 
more of the string energy is going into the horizontal plane with the 
Wapin system.  To use your argument, if the bridge pin is reacting 
the upward force of the string at an angle and 'forcing' the string 
to vibrate in a different plane, then the conventional bridge pin 
would be causing the string to vibrate out of the vertical plane 
since some component of the reaction force would be horizontal, while 
in the Wapin system the front pin offers no horizontal component of 
force to resist the upward force of the string.  In fact, it doesn't 
seem to offer any force at all to resist the upward force of the 
string.  At a low bearing angle, I don't really see what's keeping 
the string on the bridge at the front termination with the Wapin 
system.

>
>I was under the impression that Wapins bridge was conducive to 
>vibration in the
>vertical direction, not horizontal. If Rons statement  is true, then the whole
>thing becomes just that more interesting... and as I said a bit back... it
>would be nice to see the same kind of frequency data on the Stuart as is
>available for the Wapin for comparison
>
>RicB

What is this data that you're referring to?  I don't find anything on 
the Wapin website.  Therefore, it's actually rather easy for me to 
disregard it.

Phil Ford

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