Bob Hohf rote, 1/22/96: << Those who believe that greater understanding of actions is arrived at through more and more detailed quantification should take more piano lessons.>> Three pages of spreadsheets will not reveal as much about a piano as three measures of playing by educated fingers.>> There are many reason for us mechanics to take piano lessons. I didn't get started voicing until a piano teacher custmer of mine gave a sweet little Brahms intermezzo to work on. (Remember, I play jazz on a saxophone..) More important than the proof being in the pudding, the pudding is so delicious that we would be fools not to snitch a taste of the piano's qualities ( and hopefully that of our own work, also). But your point is well taken, that we piano techs are deaf and dumb if we can't experience the pianos on which we work from a pianist's perception. However when we've found what we don't like about a piano, there comes that point where we resume our role as mechanics (-forgive me for saying so lttle about that portion of our skills which nearly become an art). That's when I want to know the BW, the friction, the strike weight and the strike ratio. Measure the down and up weights and you've got the BW and friction. Measure the front weight and you get the total action mass as measured at the key touch. Measure the strike weight and you've got the leverage. These four things answer most of my questions about how the action is "hung". Ken Sloane rote: <<To sum up, I find that DW/UW specs are not nearly as important as the presence of the "right amount" of inertia in the action.>> Actually there are two kinds of resistence: inertia and friction. The first is dealt with at any change of speed (but mainly at the initial startup). The second you deal with any time there is motion at all, namely throughout the entire stroke. Presumably a pianist would like to feel in control of the key throughout the entire stroke. Friction provides this. Certainly, too low an inertia can make an action accelerate so fast as to seem spring-loaded. But that occurs at startup. From then, on friction is the control. Bill Ballard RPT NH Chapter, PTG "There are fifty ways to screw up on this job. If you can think of twenty of them, you're a genius......and you aint no genius" Mickey Rourke to William Hurt, in "Body Heat", discussing arson.
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