I became familiar with the technique of "free floating" ribs from Lew Herwig, who designed a prototype piano for Young Chang with that feature. An interesting observation I made on a piano I serviced only once: the ribs were "too long" for the soundboard. They were notched into the rim and had buckled away from the soundboard all the way from rib number one to rib number thirteen (or however many ribs there were). I don't know all the design reasons for floating ribs, but I sure saw one case in which notching the ribs into the rim was a dismal failure. Bob Anderson Tucson, AZ
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