Hi- I'd like to underscore Don Mannino's advise with the anecdote that I just finally [after removing the plate] found a buzz in a 24 yr. old concert piano that low BBB and CC brought out quite clearly. By pressing either on the first three ribs or the soundboard anywhere in that region (under the recurve in the bridge) it would cease. There were no cracks or rib separations. It was most noticable in higher humidity. It was a glob of dried shellac from when the bridge was shellaced. My guess is that it was silent for many years until that glop shrank enough pull up from the sound board and hover there waiting to humiliate the technician. Rob Loomis.
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