Hi, Vince - Here's something to try: Get another appropriately-sized damper, perhaps from a piano getting rebuilt, or from a wreck, or even make up one. It should be very close to the size and weight of the problem damper. Then use this substitute damper to experiment with; set the real damper aside and leave it alone. You can then reinstall it - no worse off than before - should you run out of time, materials, ideas, etc. Experimental ideas might include: very short damper felts, located as near the ends of the damper as possible; replace one or both trichord felts with flats (not likely, but I have seen it work); different brands of felt; steaming felts for softness (trichords can be fairly firm sometimes); one very long felt instead of two. And let us know what finally works for you! - Tom McNeil - Vermont Piano Restorations
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