[CAUT] Re: Back length tuning

[James Ellis]

Before any of you go head-over-heels tuning the back lengths of strings to
the overtones of their corresponding speaking lengths, you need to be aware
that the notion that an individual string couples from speaking length to
its corresponding back length across the bridge is a myth.  It does not,
and cannot, unless that particular bridge termination is defective.  Whole
groups of speaking lengths do couple to whole groups of back lengths by the
vibrations of the bridge, but individual coupling does not occur between a
single speaking length and its corresponding back length the way it does at
the front duplex where it merely bleeds across a single termination point.
I have found cases where a back length would vibrate at the frequency of a
speaking length of another string as much as two octaves away from it.

Sincerely, Jim Ellis