>>3. Isn't a hard glue joint a high impedence structure, more likely to >>reflect sound back, than to pass it on to the rest of the board > >Sound waves travel along the grain of the spruce, the amount of grain lost >to cracks (even huge ones) can be calculated to less than 5 % of the boards >total surface area. *in most cases* >> >>4. doesn't most of the sound get from the bridges to the outside of the >>board through the ribs anyway? > >A secondary function of ribs, the primary being keeping soundboard crown >intact. >Rob Kiddell >C.A.P.T. >P.T.G. Associate >Edmonton, AB, Canada > > > If soundwaves are travelling along the grain (which I agree they do) then how else does sound get to the outer reaches of the board, than through the ribs (and to a lesser extent the rim, depending on the design philosophy of a particular piano). I don't see this function as secondary to the crowning fuction of ribs. Ribs, it seems to me perform a series of interalated tasks that integrate nicely to allow boards to do what they do... John W. McKone, RPT Operations Manager Haugen's Pianos Twin Cities
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