Hi Terry....
Also from the same Wogram article
"From the measurements it can be concluded that the two most
important functions of the ribs are to stiffen the soundboard and to
compensate for the differences in bending stiffness parallel to and
across the grain (anisotropism). The bending stiffness exerts a
greater influence than the mass. For this reason it is more
advantageous to use narrow, high ribs than ribs with a low and wide
section."
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