Peter, Theory and Practice of Piano Construction by William B. White offers further details of soundboard construction. In U.S. the publisher is (was) Dover Publications Inc., 180 Varick Street, New York, NY In U.K. the publisher is (was) Constable and Company, Ltd., 10 Orange Street, London WC 2. My copy is 10+ years old, so the publishers listed above may not be current. Rick Clark, Miami, FL, U.S.A.
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