Paul Morris is quite correct: while the rolls and tracker bar hole
assignments were standardized, just how things were connected to the
specific organ most certainly did vary.  And, it seems to be that the
size of the organ and the room acoustics played some part in this.

There is some correspondence on a few large Aeolian installations that
mentions that the stops and division use was to be determined after the
organ was in and playing, to get the best effect.  The standard Aeolian
organ roll requirement is for 26 ranks, plus harp and chimes.  Larger
organs, in my experience, quite often only added celestes to the strings,
or ganged added strings together; but there was no major tonal change
to the basic stop requirement.

Really large Aeolians quite often had three buttons on the player:
Soft-Normal-Loud.  These only added more ranks to the specified
ones, but of the same tone color: a Dolce flute to the Concert flute,
a Trumpet to the Tuba, things like that.  If the organ had an
antiphonal division, then the duplicate ranks were simply played
together.

One has to remember that, in the original installation, the organs were
usually buried and it didn't matter -- the sound still was basically
the same, only now louder, if one can apply that term to an Aeolian
residence organ.

Some organs did not use the Pedal 2nd and 3rd Octave couplers, while
some I know did use them, and all of them were rather late organs,
1926-1930.  When this was used, the little switches were usually on
the console coupler switch board, and on one small one they were in the
console.  From a musical standpoint, it would be nice to sometimes have
an 8' Pedal, and more rare, the 4'.

One organ I know used them to add to the playing 16' octave.  Very
effective too.  However, the rolls for this organ had to have been
specially coded to use this.

Custom coded rolls from the factory?  I doubt it very much; they were
probably customized on site.  Perhaps they used the LCW holes in this
one organ.  (LCW = "Let's Confuse Welte".)  The Normal to Reverse is
used, but my experience is that this was rather seldom.

What could have been very effective would have been to have a Swell to
Great 8' coupler, for the big finish in some real "barn burner" roll;
but they only seem to have punched more holes on both manuals to get
the same thing.

The use of those two silly three-note extensions to the Great and Swell
was never clear to me.  While the consoles did have Sub and Super
couplers at times, the player did not have this, so just what their
thinking was in putting them in the Duo-Art player is a mystery to me.

If one really wants to go nuts, just try to figure out the Skinner
Orchestrator player -- a pneumatic binary computer way back in 1915,
the most complex and effective player ever to be seen.  The usual
Pedal, Great and Swell chambers, then with four or five little
short-compass chests in their own swell boxes in the Swell chamber
containing the most important Solo voices, all capable of being shifted
all over the place as the music required, and independently expressed.
The switch boards for the player were bigger than the organ chambers --
a stunning piece of engineering.

At any rate, now you see why I push for someone to write the definitive
book on the residence organ players and _really_ explain in detail how
they worked, and to be published by the Organ Historical Society.

Jim Crank