My friend and I are coming close to finishing up the construction
of two identical band organs, and we are curious as to 'key' numbering
(i.e., a Gavioli 65-key or a Limonaire 68-key).  The instruments are
played by MIDI, not rolls.

My understanding is that a 'key' is assigned for each separate function,
but that an identical note such as C5 played by two or three ranks
would constitute only one 'key'.  Clarification on 'key' numbering and
qualification would be very much appreciated.

Thanks,
Gene Kuntz

 [ I believe the term, in the context of a mechanical music machine,
 [ comes from the appearance of the iron or brass 'finger' which
 [ senses the holes and slots of perforated book music or the pins of
 [ a pinned cylinder (barrel): it looks like a key to unlock a door.
 [ The book music reader head, or keyframe, of a 68-key organ should
 [ have 68 keys in a row.  Most of them play musical notes but a few
 [ may be used to control registers or play drums.
 [
 [ The keys of the keyframe are analagous to the keys of an organ
 [ keyboard which control a varying number of pipes according to the
 [ registration commands.  However, the musical ordering of the
 [ keyframe keys is often scrambled to simplify the construction of
 [ windways to the pipes.  This is especially true in barrel organs
 [ which were later converted to play book music or music rolls.
 [
 [ -- Robbie