Andre; I think that we all understand the phenomenon as you have described it. The reason for this is as follows......... When the knobilling pin is held captive, by the knobilling pin holder, the effect of the exerted forces is concentrated in a more linear fashion as opposed to the wandering of the of a non-captive knobilling pin. Because of this if the motion, before prescribed action, is concentrated in a wave envelope conducive to excitation of a standing member the tone will change, perhaps due to framus friction. In other words Andre I can not explain what you have described ! I do know that the 'power' of repeated strokes on a given note is effected dramatically with changing backcheck catching height. With that in mind let me ask this question. Is the change in tone/power you describe on the initial blow or on subsequent repeat blows? Jim Bryant (FL)
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