Have you ever seen the slow motion video of a hammer hitting the string, and the way the damper reacts when it tries to calm the string. The red felt act as a shock obsorber between the damper head and the damper felt, and helps the damper felt seat on the string. Without it, the damper felt has to move the entire damper head, which delays its effectiveness. Although the felt can be of any color, it just happens that most damper felt manufacturers prefer red. Willem Blees RPT St. Louis
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