It's not only velocity that can be controlled. How you accelerate the key influences how the hammer and shank react, which influences the tone. IOW, as the hammer approaches the string from rest, it is how it approaches that determines the final tone. That final 1/16th of an inch that we call let-off is very definitely influenced by what comes directly before that. That these things have an influence is graphed and somewhat explained in the "5 lectures on the Acoustics of the Piano", but to determine more specifically how, is left for more research. Vince Mrykalo BYU
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