Ron N wrote: >It doesn't matter if it's possible or not. Regardless of whether the >strings are moving in the same or opposite directions, there will be cyclic >changes in string tension as the vibrating strings pass from their far >limit of excursion, through a relatively straight line neutral, to the >other far limit and back. The tension swings will necessarily pull the >bridge forward and back, and the bearing load changes will push it up and >down. . . since the vector force on the sound board is a product of the speaking length tension and the SIN of the down bearing angle. As the minute variations in the speaking length tension occur in response to the string's position (at a given point in the cycle), so too will there be a similar minute variation in the vector force on the sound board panel. In a situation where the down bearing angle is in the back length only, 'bridge rocking' (yes it will be minute also JD) will be necessary for the minute dynamic variation in speaking length tension to result in a commensurate variation in the down bearing vector force. >The bridge will move, and the soundboard will follow. I read your well conceived response earlier today Ron soon after you posted it. I too have described the motion of the string and its resultant dynamic forces on the bridge in exactly the manner in which you describe it. I understand what you're saying and agree with you. Ron O. -- ______________________________ Website: http://www.overspianos.com.au Email: mailto:ron@overspianos.com.au ______________________________
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