I haven't followed every detail of this thread, but I had a zinging note in my own piano. It was metallic sounding. I think it's also called a "sizzle". I checked the string terminations, dampers, etc. I moved every metallic thing in the room to make sure it wasn't sympathetic vibrations. I had some temporary success by repositioning the strings on the v-bar. I finally called an experienced tech in my chapter to look at it. He thought it was a voicing problem. I didn't believe him until I tried a little hammer shaping and then a small amount of needling, and the zing went away. For what it's worth, Charles Neuman PTG Assoc, Long Island
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