Let me preface this by stating that my pipe making mentor was J. Lee
Haggart, master organ builder who was first employed by the Rudolph
Wurlitzer Company in the Band/orchestra department where he made band
organ pipes.  He then applied for, and was transferred, to work under
the famous Robert Hope Jones in the theater organ pipe manufacturing
department where he became a foreman.  He moved to California in 1923
and became head voicer for the Robert Morton Organ Company.

The thing that gives the band organ its warm rich sound is the fact
that the pipes are tuned to mean temperament as opposed to a piano,
church or theater organ, orchestrion, etc. whose tuning is based on
equal temperament.  Mean temperament simply means that there are only two
or three keys that any given selection may be arranged in, eliminating
several sharps and flats that would be present in an equal temperament
scale.  Without getting too technical, in an equally tempered scale a
compromise must be achieved to accommodate 12 different keys (C major,
D-flat major, D major, etc..).

The wind-chest pressure, or water column inches, factor is the other
part of why a band organ sounds like a band organ.  Most orchestrion
and theater organ pipes are voiced at between 5 to 8 inches water
column.  Most band organ pipes are voiced at between 10 to 20 inches
water column.  There are more factors involved as well, including the
arranging compromises needed to create a band organ arrangement, but
for starters, if you want to build a band organ, best to model it from
an existing example and learn the voicing and tuning tricks from an
extant specimen.

Cheers,

S. K. Goodman

P.S. I want to thank Rick Cooley and Joyce Brite for their nomination
of me for a MMD award.  I really appreciate it!!