longitudinal mode vibrations

[Richard Moody]

----------
> From: Jim Coleman, Sr. <pianotoo@imap2.asu.edu>
> Subject: Re: longitudinal mode vibrations
> Date: Sunday, May 23, 1999 10:49 PM
> 
> Tie a rope to a door knob and then pluck the rope snear your tightly
held
> end. You will see the wave travel from one end to the other, back and
forth.
> This quickly sets up standing transverse waves in piano strings, but the
> longitudinal mode does not go away. It is when one of the longitudinal
modes
> is very close to one of the transverse modes that you will hear a very
> high sharp peak. Jim Hayes is working on additional patents beyond what
the
> Baldwin Piano Co. holds which were made by Harold Conklin when he was at
> Baldwin.

Running on imagination only, it seems to me the longitudinals would get
absorbed by the transverse.  IF they are the nodes that travel up and down
the string because it is struck in the manner of the rope under tension
tied to a door knob. However in imagination I can visualize a string under
tension quivering back and forth (like Jello) also in addition to the
transverse motions. Now this would be interesting to observe if indeed it
does exist.  But how to see it?  Which matters not so much because we want
to hear it.    Doesn't the sound board of a harp pull on the strings
longitudinaly, where as the piano and other sound boards act on the string
in the  transverse mode? Are there acoustical properties of the harp
because of this difference? 

Ric  (wondering again) 
	ps  What were the patents developed by Harold Conklin, and what is beyond
them? 

> 
> Yes, plain strings also have longitudinal modes. Their problems
occasionaly
> show up in the Tenor section mainly, but Bass strings often show these
bad
> characteristics. Incidentally, there are some good characteristics also.
> 
> Jim Coleman, Sr.
>