Ed Sutton wrote: > > If the hammer line is weighed and weighted to produce a strikeweight continuity, wouldn't that go a long way toward producing a "moment of inertia continuity" in the action stack? > > The only thing left to work on would be the "moi" in the keys, which, by our lengthy and valuable discussions on this list might represent at most 10% of the total "moi." > > (If I understand) > > Ed Sutton > > Hi Ed, I think you pretty much have the jist of the discussion so far. Course we havnt really gotten so far as to identifying just how dominate the MOI model is for the overall touchweight of the piano. And frankly, I have my doubts. Reasons ?? Well, if the present picture of action MOI is correct, then key mass is really quite insignificant, which clearly is not the case. In fact it is so to theeeee degree not the case that its difficult to see why the discussion has not touched upone what level of play sees "weight" as oppossed to MOI dominate. We all know that an assist spring action will feel very very heavy for most levels of play if the springs are disengaged. Essentially, that is to say that an action with little or no counterbalancing... with DW levels exceeding 70-80 grams is going to get tiring to play in a jiffy. In fact you have to play very forcefully, and concentrate very much on what you are feeling to arrive at the conclusion that counterbalancing is not thee domininate factor in how heavy the action plays. While it seems apparent that the MOI model for overall touchweight kicks in at some point as the determinant factor, just where and when it does so is a wide open discussion. That being the case, if we arrive at the conclusion that for significant degrees of possible playing levels the pianists sensation of the heaviness of the touch is dominated by "weight" as opposed to MOI, then small variances in key mass are most certainly going to play an important role regardless of how even the Hammers strike weight is at the key front. Taken a step further, if that is true... then small variances in inertia due to mass placement will also be far more signicant then a MOI dominate model can allow for. Cheers RicB
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