[CAUT] coupled motion and other myths

[Richard Brekne]

Hi Richard

I think the two graphs and accompanying paragraphs showing the vibration
decay for both single and double string behavior pretty clearly show
there is a difference in decay rate and character when both strings are
unmuted. Coupled motion of two or more oscillators in the same system is
clearly defined in a host of relevant physics books. books. A paper like
Weinreics assumes the reader already knows what coupled motion is.
Benades book, "Fundementals of Musical Acoustics" is an easy to read
book which describes these things nicely.  Jim Ellis has written at
least an article or two in the journal that touches on this closely
enough to get the idea as well.  I am not sure what constitutes proof
for you in this matter. But coupled motion of strings in pianos is an
established fact.

I am curious to know why you think it does not.

Cheers
RicB


    What is a "capacitive vibration probe"  Why are the measurements
    from this superseding a microphone?   How accurate is it?  Have you
    ever tried it? So where in the paper is the definition or a precise
    explanation of couplemotion? Basically, I don't think it happens in
    pianos,,,I didn't see theproof there.  Without proof there is no
    sense in believing in it.   ( wonderwhat that looks like in Latin?)
    :   )


    R moody


        Hi Richard,

        Check out the article from 1979 in the Scientific American. I
        believe it is
        titled "The Coupled Motion of Piano Strings".

        Also see this link:

        http://www.speech.kth.se/music/5_lectures/weinreic/strings.html

        And read the next two linked pages after it.

        Also try a google search on coupled motion of piano strings.

        Perhaps there has been enough scientific research done to accept
        that
        coupling of the strings does really happen.