tapping strings

[Richard E. West]

This has been a very interesting thread.  It emphasizes the need for good humidity
control in order to minimize the damage done by over-compressing the soundboard
bridges as the humidity rises.  We all know what happens with soundboards when
exposed to extreme humidity changes; it shouldn't come as a surprise that the
bridge would also be damaged.

An interesting question for me is whether piano tone may actually be enhanced by
slight indentation of the bridge tops.  We all assume that the termination should
be sharp and clean, but given the history of the piano, it's reasonable to assume
that no one really researched that supposed fact.  Would it be out of the realm of
possibility that the tone is positively affected by a fuzzy termination at the
bridge, possibly damping undesireable harmonics?   How many pianos have been built
without the standard wood bridge configuration?  Is there a bias against a
soundboard bridge that is not wood or has a cap that might be metal, for example?
In any case with time, the termination may become too fuzzy to produce good tone,
but initially, what is the effect?

Secondly when a piano is restrung common practice nowadays to to get rid of the
indentations, and refresh the notching.  I've often wondered what this is doing to
downbearing.  To me the depth of the bridge indentation might be a measure of the
extremes of humidity that the piano has been subjected to.  If you take out the
indentations, you're taking the bridge cap down to the lowest level and changing
the bearing enough that there actually may not be enough bearing during dry times.

Thirdly, how does the alleged "bridge roll" affect the bridge.  Does it exacerbate
bridge damage or does it somehow reduce it by allowing the bridge to "roll with
the punches" so to speak?

Richard West
University of Nebraska