Hi Ron Enjoyed your usual succinct and clear technical thoughts on the subject of recent interest on the list.I n your current catalogue of various soundboard forces senarios you mentioned that in the pure forced crowned board, only the compression of the panel is creating the crown and that the ribs being flat are actually resisting that effort which I agree but as to downbearing I have this thought. I no longer think that the compression of the panel is the only force opposing the downbearing in this type of construction..I have heard that some who use this method allow the boards to puff up a bit before glueing them to the rim which does bend the rib further I,m thinking 40% R.H..Once that bent rib is anchored in the case the ends can no longer move as much..It,s true that they can unbend some of course as the panel shrinks or cracks or even self destructs but I have so often removed boards the had some crown with strings removed that once off the rim totally flattened out . My point being that those force crowned ribs once glued in position where an essential part of the equation in contributing to the resistance of downbearing and also because ofthat making tonal contribution.what do think ?Also all those pianos from the past we admire so much all used a procedure we all no longer think wise to embrace. But wow they really sounded great.! sincerely Dale Erwin
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