Tuning a band organ takes time and infinite patience.  I suggest wearing
a pair of ear protectors, similar to those worn by heavy equipment
operators or those who work on jet plane runways.  You will be able to
hear the notes clearly through the ear protectors, and the ears will
not become tired and loose perspective on your tuning ability.  This
can occur if a tuner is exposed to very loud tones for an extended
period of time.

One must have a thorough understanding of the tuning layout and use a
well marked tuning/test roll to prevent becoming disoriented and tuning
the wrong note.  Some ranks of pipes on band organs play in unison
(Wurlitzer 165) and cannot be turned off while tuning, therefore one
rank must be muted while the first rank is tuned.  To accomplish this
attach a chicken feather to a long stick and insert the feather into
the mouth of the pipe that requires silencing while tuning the unison
pipe ahead or behind it.

If one is not accustomed to setting a temperament, an electronic tuning
device such as Yamaha tuner can save time and be used as a quick
reference when going back over the tuning to check for changes.  The
tuner must be aware that tuning a band organ will never be absolutely
perfect.  The pitch will change as the air churns within the chests,
and can change the air temperature which will effect the tuning as one
progresses.  Go over the tuning several times, and observe if the pitch
is going sharp or flat, during the time you are working.  Using this
information, make adjustments on the electronic tuner and proceed using
the adjustments as a reference point.

Use the motto: Do your very best and walk away.  The tuning will
never be perfect, and the slight imperfections in the tuning of these
instruments are what give band organs a quaint bit of character.  The
general public hasn't a clue if an instrument is in perfect tune or
not.  They will love it, even if you hear some slight errors.

Bruce Clark