hammer/string interaction

[TUNERJIM@aol.com]

Stephen & List,

     Some years ago (12 - 14) Kimball brought some ulta-high speed motion
picture
photography of a bass hammer striking a string. Clearly the origination of
the
fundamental was shown as well as the strking of the hammer by the string, two
or three times by the fundamental and the 1st harmonic. Obviously energy was
transferred back to the hammer by the string.  Not long after seeing this
film I
encountered a Yamaha grand which had one bass note appreciably weaker than
its neighbors.  Remembering the Kimball film, and the dramatic hammer shank
flexion,
I lightly sanded the hammer shank to make it more limber and, presto, the
aural
strength of the sounded note increased to that of its neighbors.  I took this
as
an indication that I had decresed the reverse transfer of energy by
facilitating
the return of the hammer and thus reducing the number of string to hammer
hits.

     (For those of you who haven't seen this or a similar film, the bending
of the
shank looks exactly like the bending of a fly fishing rod when the angler is
casting.)

     If you have, or can get, access to this film I recommend you do so.

Regards,

Jim DeRocher