Hi all,  John Buscemi's problem is a subject that I also struggled
with.  I have a 1928 Steinway LR grand, which I also meticulously
restored.  (I have to assume that John's piano has an expression box
like my later model does.)

I found that when the accordion dynamics were set up according to
the original specifications, the piano played way too loud at higher
intensity levels.  So after setting the minimum intensity so that it
just played notes without dropping out, I modified the travel of the
accordions.

I found that reducing the accordion travel proportionally still gave
me the complete dynamic range but that it was "compressed" so that the
loudest notes did not drive me out of the room.  I had to make longer
screws so that the "8" accordion sections could not travel as far and
then I transferred the old "8" screws to the "4" section, etc.  When
I was done, I had reduced the travel of the "4" and "8" sections by
approximately one-half, the "2" section a little less and almost no
difference to the "1" section.

After making these changes, I used my water gauge to measure vacuum
level at each intensity level and plotted a smooth curve, adjusting
the screws, as needed, and then checking the results with rolls.
I also disconnected the crash valve, which some pianos don't have.

If John or others would like more details, I would be glad to talk
personally, email pictures, etc.  Just email me your phone number.

Pat DeWitt
Ft. Wayne, Indiana