Paul Morris' description in MMD 020709 on the 176-note tracker bar
scale used for the bass notes is great.  The description of the test
roll helps to answer the question about using 13 holes (C to C) on the
tracker bar.  It is interesting to me that it was probably done this
way because of backward compatibility between the older 58-note roll
days.  I understand that Aeolian used some of the older 58- and
116-note rolls to make the newer 176-note organ rolls.

This description agrees with the one that I got from Tim Rickman back
in December, 2001.  Tim reported that the 1st octave notes 1-13 go to
notes 1-13 of the Pedal Division.  The 2nd octave relay transferred
notes 1-13 to notes 13-25 of the Pedal Division and the 3rd octave
relay transferred notes 1-8 to notes 25-32 of the Pedal Division.

The test roll doesn't test 2 conditions which are note 1 (hole 31) for
the 2nd or the 3rd octave.  These may have been skipped on the test
roll so the notes would play up the scale chromatically and could be
easily detected by the person running the test.

Pete Knobloch
Tempe, Arizona, USA