A retired prefessor of engineering who is an expert on sound transmission and absorption, and an author of a new text on this subject suggested to me that using a dense rubber, such as inner tube rubber, afixed to a vibrating object will dampen the sound considerably. Maybe a layer or more could be glued, or tightly wrapped to test this idea. Haven't tried it on a piano, but it sure works wonders on ABS drains! Ralph Thorn
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