Isaac, In some cases, one can retain the original damping material, (felt). However, a proper RESTORATION allows replacement, but only with similar materials. Sometimes it is more difficult to find something like the original materials, but it can and should be done. The reason is that the over-all sound of the piano will drastically change if the damping system is modernized IN ANY WAY. When replacing strings, one cannot be exacting in the placement of the new strings, (as opposed to the placement of the olde strings), So.....it is necessary to use new, exact replacement material. If any "modern" type felt is used, you have lost the original "Sound". IMO, performance be damned. Most "performers" have less of an idea what the piano sounded like, than we do. (AND....to be sure we are guessing, albeit an educated guess.<G>) I hope this is clear, for you. If one cannot try to reproduce the originality of the instrument, then it is my opinion, that the tech should leave it to someone who can. OR....leave it alone. Best Regards, Joe Garrett, RPT, (Oregon) Been There, Didn't Like It, So I'm Here To Stay! [G}
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