Phillip Ford wrote: > > 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. I would think the two are rather interlinked.... tho you know me and my speculative way of thinking things through :) Still... lets loosen every thing up a bit.. string tension, stiffness of the bridge pin and bridge... let things reaalllly move around, and take it all in slow motion... walk me through what happens here ol ?? We start off with that hammer smacking into the string causing that first initial pulse (which can we assume is primarilly vertical oriented ... yes).. what happens when it hits that overly flexible bridge and pin .. both the horizontal and the angled at 10 - 20 degrees ? What happens if we go to the extreme of taking a rope, terminating it both ways... giving the rope a vertical whip... ? I guess I'll have to try this out and see for myself.. but if in the macro vision condition there is a deflection that corresponds to the angles of the termination... then that same should hold in principle no matter how stiff things are... since they can not be infinantly stiff...... only the degree of the effect should change... yes ?? > 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. > Bring your stiffness issue back into the picture, along with side friction on the pin and the fact that the second and third bridge pins takes care of the brother part of keeping the string locked down with Wapin,,, I certainly see whats keeping the string down... but what I dont see is why this results in more of a horizontal vibration tendency as evidently they claim...... must be looking at it wrong I guess. :) > > > > >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. > You are right... they dont have it available anymore... used to be up for public view... lots of charts with some frequency comparisons between a Wapinized Steinway D and a Stock one.... showing sustain and power for each. I'll see if its possible to still view these. RicB > > Phil Ford > _______________________________________________ > pianotech list info: https://www.moypiano.com/resources/#archives -- Richard Brekne RPT, N.P.T.F. UiB, Bergen, Norway mailto:rbrekne@broadpark.no http://home.broadpark.no/~rbrekne/ricmain.html http://www.hf.uib.no/grieg/personer/cv_RB.html
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