I've been musing lately.  Has anyone done a study of the relationship
of bellows volume, stack volume and supply hose size?  Is there an
optimum ratio such that valves seat firmly and suction remains stable?

For instance, a supply hose that is too small would limit suction to
the stack; too large, and the suction changes too fast.  If the supply
hose is too small and valves are not sucked down as firmly as optimum,
then no matter how well designed the valve, it would not be efficient.
Perhaps, then, the solution is not to redesign valves but increase
supply openings.

If there is a perfect ratio, is it absolute or is a large variation
allowable?  Were players designed by formula or trial and error?  Was
there a perfect player built?  One last question, can or should we
modify players towards a perfect ratio?

Maybe I've been tuning too many pianos lately, and the mind may be
wandering too much. 

Jeff Davis