Michael, Ron, etal, I've been following this thread with interest, and thinking about some of the concepts. One piece of the explanations for the observed effect of the multi-species laminations doesn't make sense to me, and I wanted to run it by you all. Regarding Michael's experiment, ie, three identical pianos with three different bridges, 1-solid maple,2-maple with mahogany laminations, and 3-maple with mahogany and ebony laminations... The explanations for the observed effects all seem to point to the effect of increased density/mass. Here's my question. In the 2nd piano example, maple and mahogany laminations: since the specific gravity of mahogany (swietenia macrophylla= .51) is actually less than that of maple (.63), this bridge is actually less dense than the stand alone maple, assuming absolute density is what we are looking at. To my mind, this doesn't jive with the straight-up absolute density explanations...unless... the effect of increased density occurs as much from the layers of non-uniform densities introduced by layering different species (with differing densities), as from the actual absolute densities of the woods. Does this make any sense? Jim I
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