Scott Murphy recently completed a high speed video demonstrating the cause of damper oink when una corda is used (and shifts the hammer off the left string). Very revealing. It has to do with the fact that the unstuck string vibrates sympathetically with the others, but out of phase with them.
https://my.ptg.org/ptgeducation/discover-more/hsvideo
Scroll down to the bottom of the page.
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Fred Sturm
University of New Mexico
fssturm@unm.eduhttp://fredsturm.nethttp://www.artoftuning.com"We either make ourselves happy or miserable. The amount of work is the same." - Carlos Casteneda
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