There are several other situations where strip muting is difficult, including most uprights above the treble break to the end of the dampers. I carry a strip, 18 inches or so, of key bushing cloth. This is inserted in the small space between center string and either left or right string, leaving the other outside string open. On uprights, even spinets, there is usually just enough space between the tops of the dampers and the bottoms of the hammers in striking position to accomodate the strip. This may also work on birdcages. Heaven forbid you should have any, but it is also handy for Balwin Electropianos! Tom McNeil, Vermont Piano Restorations
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