Hi David A couple comments below to your fine post. "David C. Stanwood" wrote: > > > > >Best thing so far is Stanwoods Method. Tho it does not directly deal > >with inertia issues, it does insure very even key to key inertia > >characteristics. > > >RicB > > Richard, thanks for the support, Tho I do deal with the inertia issue by > matching hammer weight and ratio. This does, in a crude but effective way, > deal directly with inertia. For instance, we know pretty well from > experience what combinations of hammer weight and ratio will produce an > action dynamically appropriate for the customers needs. For instance if we > find an average weight ratio of 6.0, I wouldn't go with a Strike Weight > level above 1/2 medium unless the client wants a heavier-than-average > action. For a medium dynamic feel with a 5.5 ratio I would specify a top > medium strike weight. > I should perhaps have clarified what I meant by "does not directly deal with inertia" There is nothing built into your formula or method that directly justifies any ratio to strikeweight matching. You formula simply states what results from given action parameters. That in itself cannot be used as any "proof" that this or that configuration is inherently better then another. What your system DOES allow for is a very systematic quantification of exactly the static parameters that result in a given Balance Weight, which in turn allows us to place our cumulative expereriences in that perspective. But in the end, you base your recommendations for strikeweight to strikeweight ratio matching on subjective analysis of experience. The apparent shift in matching reccommendations since the release of your Smart Chart a few years back underlines this. Not that thats a bad thing mind you. The sense in which your system addresses the inertia issue is more a by product of creating even static weight curves, and the by product of resultling total MOI and its componet hammer(and shank) and Key MOI. But you do not purposefully quantify and design into an action any particular levels of MOI. Nor do I think one really needs to... which was the point I tried to make to Fred Sturm and Ed Sutton the other day. It would probably be good to quantify those moments and compare them to what results in any given Stanwood configuration so as to have a better idea of exactly what kind of inertial characteristics result, but that is more for a general understanding of action dynamics more then for practical application. That said, I suspect that if a method was contrived for doing basically what you do, and as easily.. but directly relies on MOI as integral part of the equation, would be the next step in any touchweight designing effort. Whether or not thats doable is another matter and remains to be see. > > There is no substitute for measuring and knowing the hammer weight or > strike weight levels and this should be (and is becoming) part of the > accepted discipline... It would be so helpful if every time we mentioned a > hammer as being "light" or "heavy" to qualify the meaning of those terms by > refering to the specific weight zone: I agree, and have said so repeatedly. The Stanwood metrology is the easiest and most effective (by far and away) way of communicating action parameters, and should be <<must>> reading IMB for any serious minded pianotech. > > http://www.stanwoodpiano.com/SW-HWstandards3.pdf > > Just some thoughts... carry on! > > David Stanwood > > _______________________________________________ > caut list info: https://www.moypiano.com/resources/#archives
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