HI all,  Jon Page's comment about dampers and sound board impedance
made me look in my reference books on piano design and construction.
I guess my books are too old because none of them mention sound board
impedance.  Now I'm wondering if the term existed in the 1920's?

Jon is definitely right about the amount of information in the PTG
archives, but I couldn't find anything directly relating sound board
impedance to the optimum (or most desirable) location for the last
treble damper.

Musically,

John A. Tuttle

 [ Search for "soundboard impedance" at
 [ http://www.ptg.org/archive/pianotech/
 [
 [ The impedance match, hence the energy coupling, is what affects
 [ the natural damping of the sound.  If the instrument has little
 [ coupling then the sound sustains itself longer in the string, 
 [ and greater damping effect is needed from the damper mechanism.
 [ I suspect that the bridge crown, and placement relative to the
 [ edge of the soundboard, are the piano designer's best way to
 [ balance the natural damping and volume of the modern piano.
 [ -- Robbie