A few cents...ladies and gents, I've heard before that Hamburg pre-crowns ribs, but this was contradicted by Hartwig inside the factory. I would love some confirmation, Ric, and any other juicy tidbits you might be able to extract. I understand they're a lot more open in Hamburg than NY. As for Steingraber, they seem to be the only company that is really trying to preserve a dome shape to their boards. Not only do they glue a pre-crowned treble bridge to an unribbed board, they also custom fit the rim all the way round, which makes more sense than assuming a 1 degree angle on three sides will yield anything except more stress (not that I'm saying more stress is undesirable). The Germans seem to have done copious research on stress in soundboards as a tone-producing ingredient, according to Sauter. There are many texts in German which have yet to be translated into English. The Steingraber bass bridge is attached after the board is installed because of the many centemeter variations in the plate casting. The bass bridge is therefore hallowed out at the root to allow it to flex onto the crown of the board. Regards, Jude Reveley, RPT Absolute Piano Restoration, LLC Lowell, Massachusetts (978) 323-4545
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