I have an original factory 80-note Steinway Duo-Art Grand stack.
I noticed that while the division of these stacks is supposed to be
40 notes in the base and 40 notes in the treble side of the stack,
this stack has a division of 39 notes in the bass side and 41 notes
in the treble side.

While I thought this might have simply been a mistake at the factory
in terms of placing the divider in the wrong place on one of the three
pneumatic decks,  I note that the bleed bar is also divided in a
40-note/39-note configuration.  Thus, if this were merely a mistake,
why would it be repeated in the separate manufacturing of the bleed
bar?

I checked the stack described above against the other stack that I
have, which is identical to the stack above.  I was surprised to see
that this stack also, (again, this other stack is an 80-note Steinway
Duo Art Grand stack), has the unequal division of 41 notes in the
treble and 39 notes in the bass.  Obviously this was either
deliberately designed into the stacks, or, for some reason, the result
of a design error.

Has anybody come across this problem before, and/or does anybody have
an explanation for it?

Thank you for your help.

Barry Dennis

 [ The Duo-Art system was an extension of the Themodist accenting
 [ system and so could play Themodist rolls.  The bass/treble split
 [ of my (American-built) 1917 Stroud Pianola with Themodist system
 [ occurs between E-flat and E above Middle C, so 43 notes respond
 [ to bass Theme commands and 45 notes respond to Treble commands.
 [ I believe only Ampico placed the split point exactly in the
 [ middle of the 88-note scale.  -- Robbie