Poison-pen Bill B jabs: >You got the ones with the sodium pentathol. Next time it's the >Haight-Ashbury recipe. <g> He he. >It would be nice to have some values (maybe next time the green >flecks AND the sodium pentathol). Yummy. Green flecks. Parsley cookies. > Knowing how the values are observed/measured would allow us to see >what scale the graph is in, ie. are the breakpoints plotted in the >neighborhood of a "mp" or a "ff". Then we'd know over how much of >the pianist's dynamic range, the application of counterbalancing >mass works for or against pianist's control. To re-iterate my response to Ric and Phil, I agree - some numbers for these various parameters will be worthwhile at this point. >As the mathematicians say, complex. I think the engineering studies >are going to have to remove the pianist from the piano, to avoid >contaminating variables and unknowables. Maybe, Stephen, you've been >there done that already..... Well, yes and no. I agree the analysis needs to be objective, and can be simplified considerably to use only basic physics and still yield useful results. But, I also think that experimental work both with and without pianists will be absolutely necessary before any sort of meaningful conclusions about real pianos can be made. The bottom line is that "control" is something that a pianist undestands intuitively, so this aspect must be taken into account in the analysis. The trick is involved in setting up experiemental scenarios that can provide objective data. >The original choice is not between steep or shallow, it is between >choosing or not choosing. Like the original sin, it's not which sin >you'd pick, but whether you're going to be a "sinner". Nice way of looking at it. >Don't forget the rep and the shank. If you don't want mass in the >key, you don't need it in these either. I would like to see a real >hammer out on the business end of this action. >As soon as the optimal slop has been decided upon, designing the >action should be straight forward. Yes. I agree...provided a single desired slope and intercept is decided on. It's then easy to find appropriate static and dynamic balancing that achieves the control graph. Thanks again for the cookies Bill. Stephen -- Dr Stephen Birkett Associate Professor Department of Systems Design Engineering University of Waterloo Waterloo, Ontario Canada N2L 3G1 Davis Building Room 2617 tel: 519-888-4567 Ext. 3792 PianoTech Lab Ext. 7115 mailto: sbirkett[at]real.uwaterloo.ca http://real.uwaterloo.ca/~sbirkett
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