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 Force Versus Distance of a Pneumatic
 By Robbie Rhodes
 
 
 | Has anybody any numerical data on how the force of a simple "board"  pneumatic varies with the opening?  I've derived an equation, but  it's fairly complex and I'd sure like to check it with actual  measured numbers. 
 This data is needed to describe the effect of the hammer-lift  "Soft Pedal" in a grand piano reproducer.  When the hammer rest  rail is lifted it cuts the hammer travel distance to one-half.   If the pneumatic force were constant that would result in 3  decibels of sound volume reduction.  But my ear and microphone  indicates its actually more, and the reason is because the  available pneumatic force is much less as the device closes.
 
 -- Robbie Rhodes
 
 
 |  | (Message sent Thu 21 Mar 1996, 04:49:55 GMT, from time zone GMT-0800.)
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