In response to Pete Knobloch's question (080101 MMDigest) about
the sequence of events that occur as the crescendo pedal is depressed,
I offer this expanded explanation.

First, I must give a bit of background.  Most of us who study the
operation of various mechanically played instruments realize that these
instruments evolved.  The key now to sorting out undocumented changes
lies in the rolls or book music.  Recently, Art Reblitz discussed the
Berry-Wood A.O.W. tracker scale.  He used an existing roll to logically
ascertain functions of some of that tracker scale.  But lacking
additional rolls, that scale still has unsolved mysteries.

A few days later, Jim Crank proffered a plausible explanation of the
meaning of "L.C.W." tracker hole assignments on the Aeolian Duo-Art
Organ scale.  But in that instance, the explanation lacked the strong
confirmation from actual roll coding.

Also recently, there has been discussion about the function of the
Aeolian 116-note console control functions.  The answers posted on
those questions were based on both known console wiring and the
instructions found on the rolls and roll catalogs.

Continuing the analysis of those 116-note rolls, it must be realized
that Aeolian was evolving from the reed organ business into the pipe
organ business.  Aeolian skillfully used its huge roll library for the
constantly evolving business.  Successful 58-note rolls were upgraded
to 116-note format and then later to 176-note format.  And to take full
advantage of the huge library, Aeolian made its pipe organs backwards
compatible.  The early Duo-Art organs could play three rolls formats
making thousands of titles instantly available to those first
customers.

The early 176-note rolls retained some of the limitations of the reed
organ instruments.  Aeolian initially continued to use the "Reverse-
Normal-Unison" tracker coupler in the Duo-Art Organ rolls.  Since the
pipe organs were "electro-pneumatic" and the reed organs were pure
pneumatic and mechanical, the reed organ limitations for switching
could be left behind as the pipe organ business evolved.  The newer
Duo-Art rolls abandoned some of the switching matter by merely punching
the rolls so that no switching was required.

Like the 116-note rolls, the early Duo-Art organ rolls have stamped
instructions giving stop changes and crescendo pedal positions
throughout the length of the roll.  In Aeolian parlance, the crescendo
pedal is called "Tonal".  Instructions may give an instantaneous Tonal
movement, such as, "Tonal on Full", or a time based movement, "Tonal on
Gradually", followed by the point where movement stops, "Tonal on 1/2".
The consoles have a tonal indicator at eye level graduated in 1/4
increments.

Since these early rolls contain the printed instructions, one can see
the code (stop) perforations that correlate to the words.  Once again,
the rolls are key for gaining insight into the original intent.  The
scheme for turning on the stops as the crescendo is depressed is as
follows:

CLOSED

GT STRING P
SW FLUTE P       SW TO GT COUPLER
SW STRING PP
SW HIGH FLUTE
PED FLUTE P      GT TO PED COUPLER
GT FLUTE P
SW STRING P
SW STRING MF
SW STRING F

1/4 ON

GT HIGH FLUTE
PED FLUTE F
SW STRING VIB
VOX
OBOE
GT STRING F

1/2 ON

GT CLARINET
PED STRING
SW DIAPASON MF
SW DEEP FLUTE
GT DIAPASON

3/4 ON

PED BASSON
PICCOLO
SW TRUMPET
GT TRUMPET

FULL ON

GT = Great or lower manual
SW = Swell or upper manual
PED = Pedal

The above schedule is not perfect.  Some stops may be slightly out of
order within each group.  The information is from the rolls and my own
console wiring.  My console activates the couplers and these are not
mentioned on the rolls.  Notice that the organ's softest GREAT stop,
GT STRING PP, is not in the schedule.  Thus the schedule includes 25
stops.

Since the schedule of crescendo pedal activation is instrument
specific, logical substitutions should be made if different resources
are available or listed stops are missing.  Instructions in the roll
catalog tell the user that their particular installation will be fully
used when the tonal is full on.  Thus unlisted stops such as "Sting
Mixture P", "Quintadena", and others will be heard and bring the organ
to full volume.

The standard Duo-Art stop list contains 26 stops plus "Echo" stops
which generally contain three or more stops.  Aeolian built many organs
much larger than this 29 stop configuration.  Many organs had 70 stops
and the really big ones go over 100.  Most of these large installations
were the beginnings of today's surround sound.  Various divisions of
the organ were located on all sides of the music room and when full
organ was employed, the listener was totally surrounded by the rich
Aeolian voices.

One Duo-Art roll theory I am working on is that when the "Echo" is
coupled to the Swell, the Echo is to play as a solo.  If the "Echo" is
coupled to the Great, it is meant to join the Great for a more robust
chorus sound.  Another possibility is if the "Echo" is coupled to
either Swell or Great and the Tonal is on full, the Echo is _not_ to
play as a solo.  Conversely, if the Tonal is off, the Echo is always
meant to play as a solo.

Since post touches on the Aeolian Organ roll formats, I would like to
clarify two popular misconceptions:

The Aeolian pedal notes are derived from the bottom _13_ notes (not 12)
of the lower tracker holes.  It is a full octave, CCC through CC.

The 116-note rolls don't all predate the Duo-Art rolls.  New issues
of 116-note rolls continued into the 1920's, and many of these late
rolls are hand played and have Duo-Art counter-parts.  The Duo-Art
counter-part rolls in these cases are not upgraded 116-note rolls.
Rather, the converse is true.  These late 116-note rolls are stripped
down versions of 176-note Duo-Art rolls.  The stripped down version
carries no artist name on the leader, yet the holes line up perfectly
when laying one roll over the other.

Bob Taylor