David writes: << Why wouldn't you want the minimum friction to occur the slowest rising rate of the key, the beginning of the stroke? The momemtum of the key will compensate for increasing friction later in the stroke. >> Two reasons: I think it best to have the least amount of friction and maximum ratio at the point of finest control, (escapement). The zero friction at this point assists control at ppp and the higher ratio provides maximum power at FFF. Reaching the the magic line at let-off provides this. The difference between maximum friction occuring at the beginning of the stroke or half way to the magic line is not measurable, but the difference in ratio is. So, why create a fall-off in the acceleration to avoid an immeasurable change of friction? I think friction's effect increases with speed, thus, placing it at the lowest speed in the event will minimize its effect. At this point, the major resistance is the inertia of the action parts. If the magic line is reached at let-off, what we have is friction decreasing and the ratio increasing throughout the stroke. Splitting the path on either side of the magic line creates a situation where friction begins to increase and the ratio decrease as we reach let-off. This can't be good. The same concept of steadily increasing ratio can be seen in the original idea behind Steinway's accelerated action; with the half-round slightly off-set proximally, the key ratio increased as the key was depressed, due to the fulcrum effectively moving towards the performer. In later production, the half-rounds appear to be drilled in the middle, thus negating the effect. Regards, Ed Foote RPT http://www.uk-piano.org/edfoote/index.html www.uk-piano.org/edfoote/well_tempered_piano.html <BR><BR><BR>**************<BR>A Good Credit Score is 700 or Above. See yours in just 2 easy steps! (http://pr.atwola.com/promoclk/100126575x1220439616x1201372437/aol?redir=http:%2F%2Fwww.freecreditreport.com%2Fpm%2Fdefault.aspx%3Fsc% 3D668072%26hmpgID%3D62%26bcd%3DfebemailfooterNO62)</HTML>
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