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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