Ken Sloane left this message: Mike at Cincinnati: The rationale for my saying that not much information is derived about inertia by using touchweights while measuring acceleration in a key/ham system came in the next sentence, though (I must admit), I didn't make that very clear. Let me be more thorough. I said in that next sentence: "Pianos I have encountered with lots of inertia seem to be fine for the pianists until they play them fast and loud. At that point, all the inertia in the piano becomes a problem for the pianist as they try to accelerate/decelerate the key/hammer systems very quickly many times persecond". In other words, I don't think we would see much difference in acceleration rates between pianos of high and low inertia until we tried to accelerate them -- i.e. their key/hammer systems -- very quickly as occurs in fast, loud playing. I've been thinking about this over the last several days. The purpose of wanting to look at angular accleration is for my diagnostic purposes. My experience is frustration with mostly Steinway actions that have been retrofitted with new parts. You can achieve good Weight and Friction values and still have an action that is unsatisfactory. If I think back over the last 12 years here I have to admit that there are just as many complaints about actions that are too easy to play as there are about ones that are difficult. Ken: We have to invent some sort of spring loaded machine that could engage notes rather forcefully but, of course, at the same force from piano to piano to analyze inertia because its presence, as it relates to the pianist in a problematic way, is not felt on soft blows. Obviously the touchweights mimic a softer than soft blow. Let me point out that accleration is entirely independent of the speed. This means that using the method I described in my original post it will not matter what gram weight I use to make my measurements. Michael Wathen College-Conservatory of Music University of Cincinnati
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