David Love wrote: >I don't like to use assist springs for more than about 9 - 10 grams of BW, >or the effective weight of the wippen. I don't like the wippen to be >lifted >too much. Just floating is as far as I like to go. At 15 grams I find >that >I don't like the feel of the action. Nice musing as usual David. :) The reason I ask is that I see a lot of variance in this assist spring issue, and for that matter whether or not the spring should be used at all. And all this goes really back to the hammer mass / FW amounts discussion. Jan Grossbach is one of Klaus Fenner's buddies. Together they have just written what is probably to date the most complete piano designers textbook. Jan is an opponent of David Stanwoods ideas, and largely bases this on a general opposition to assist springs. He takes the position (as I understand it) that says whippen assist springs should only do enough work to even out Downweight variations, and that these should be so accurate to begin with that assist springs are really superfluous. This is in principal not too awfully distant from your own observations about the difference between Stannwoods inertia priority frontweighting and the older BW priority weighting. Course you take the position that whippen assist springs could also be used to lower BW somewhat and Jan G doesnt go along with that at all. Course he is not alone. Steinway Hamburg, Schimmel, and a bunch of the others over here dont employ the whippen spring. Recently I took apart a Schimmel 6 foot Grand and found hammer SW's ranging from well over 14 grams to just about 8. I found over 65 grams of lead in a few keys. Now THAT's what I call massive amounts. In anycase we see that the field of play here is quite large indeed. Ranging from heaviest hammers of 14 + grams to 10 or below (McMorrow suggests less I believe), heaviest FW's ranging from nearly 70 grams to perhaps as little as 15 grams (perhaps less ?) and assist springs doing 20 (+?) grams of lifiting down to "they should not be used at all". I suppose this is one of the reasons my own choice is for what appears to be in the middle of all that for the average mean piano, tho I end up a tad on the heavy side as I am not a fan of whippen assist springs. I just think thats one more adjustment / weight contribution that can go bad or be mucked up by an inexperienced hand and that it is simply not neccessary in most cases to achieve very good and appropriate results. I like to give manufacturers at least some benifit of the doubt, and wonder then why they choose to seemingly ignore Stanwoods thoughts, or McMorrows for that matter. They still use what equates to rather uneven SW curves (notable exception is Steinway Hamburg over here) and the old style of Front Weighting. Some dont even go so far as to start off with any kind of pattern leading. At best this results in an even static Downweight. So WHAT basis is there really that this is to be prefered then other priorities looked at by McMorrow, and then Stanwood, and no doubt others who have not formalized their thoughts for the rest of us to read about yet ? And for that matter what real basis do any of us others have (other then what amounts to personal tastes and opinions) for what we choose ? As far as I know Stanwood, and to some degree, tho on a different tangent, our Russian friend Alexander Galembo are the only folks too formally look into the matter and their results are quite different. Richard Brekne RPT NPTF Griegakadamiet UiB
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