----- Original Message ----- From: "Ron Nossaman" <rnossaman@cox.net> To: "Pianotech" <pianotech@ptg.org> Sent: Sunday, August 14, 2005 8:30 AM Subject: Re: string termination >> A lot of things about string terminations have bugged me for some time. > > Me too. > > >> Stuart of Australia claims that their bridge termination increases the >> vertical vibration of the string. Hmmmm? How does that effect the >> sustain???? > > I don't think the termination has anything to do with sustain in this > case. The kilo of brass mounted on the bridge in the form of agraffes, > however, will help sustain substantially. Thanks, Ron. I had forgotten the impedance factor in all this. Can't we make the whole bridge out of brass???? And really sustain????? >> My esteemed colleuge from one of the fly over states suggests that a >> string starts out vibrating vertically, slowly starts to drift >> horizontally but never gets to true horizontal. He also suggests that a >> string tends to vibrate at 90 degrees of its termination. I want to find >> out if that is true. > > "Flyover" sounds like I might qualify for comment here. I'd like to find > out if it's true too, but a string stretched across the garage isn't going > to be the real thing. I'd like to hear what you observe anyway, as at > least a beginning of understanding what cause and effect relationships are > at work. Part of the question here for me is what affect the moving bridge > has on string excursion direction. In Stuart's setup, both terminations > are horizontal so a vertically cycling bridge shouldn't disturb much. Both > the "standard" pin configuration and Wapin have a horizontal termination > at the agraffe (etc), and a vertical or near vertical termination at the > bridge. I would expect a vertically cycling bridge to have a greater > effect on these. Then too, the bridges are all these systems are rocking > fore and aft, only the rocking motion won't be exactly along the string > line because the bridge isn't perpendicular to the string. The motion will > instead be left-forward, right-back in a grand.. >> Here's my question: A vibrating string has two terminations. It is >> excited in the northern direction. (Ignore the strike point) What >> effect on tone will be the termination of the two ends of the string????? >> Both north, one north and the other south, east or west???? Or no big >> difference?? > > Too general. Define termination. Are you talking mass, rigidity, hardness, > shape, direction, or all of the above. There are a lot of variables here. I want to get rid of all the variables but one. It's none of the above. Only when I have reduced the variables to the minimum and reached a conclusion, will I add more variables. If I can't reach the conclusion I want, I'll do like all good researchers and terminate the project and lie about the results. I'll describe my project: My subjective intent is to build a monchord. Might as well use a speaking length of a typical note and standard tension. There will be just two termiinations that will be the variables. No bridge, no soundboard to fog up the results. The string will be observed at a 45 degree angle at various points of the speaking length to get an idea how the string vibrates at different angles of termination. The 45 degree obvervation is necessary to get a three dimention view. How well my strobe works and at what high frequency will determine the progression of the project. > > If some of you deep thinkers have an answer to my question that > makes >> common sense, I won't have to do this. Give me your feedback. Thanks > Come on Carl, you know "common sense" is an oxymoron. As a farm boy, would horse sense be more appropriate??? At least horses have it. Carl Meyer PTG assoc Santa Clara, Ca. > Ron N > _______________________________________________ > pianotech list info: https://www.moypiano.com/resources/#archives >
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