Matthew Caulfield wondered, in MMD 19.10.26, why some Wurlitzer 165
band organs were converted to play the more restricted Caliola roll.
By the time Wurlitzer offered this option around 1940, Wurlitzer's
band organ business and music roll arranging was about done.

A few years earlier, Wurlitzer's new band organ style 165 arranging
had been reduced to one or two new rolls each year, the rolls limited
to only six tunes per roll (although numerous repeats made them the
length of a 10-tune roll), and operators of the few decent organs
remaining cared little about the greater musical qualitative of the
165 scale capabilities, and were more concerned with providing more
and contemporary music, lower costs, and less maintenance.

The Wurlitzer Automatic Player Piano -- APP -- and the similar Caliola
scale provided the answers.  It was exactly the same size, with 75
tracker holes, and would fit perfectly on the spool.  For every Style
165 roll issued, about four APP or Caliola rolls were issued with
a full compliment of 10 tunes, providing more frequent, contemporary
music.

The rolls sold for about $25, compared to the $65 cost for 165 rolls.
In those days, operators and customers cared little about the greater
musicianship on the older 165 rolls with so many diverse pipe registers,
greater percussion options, and interesting creativity.  Most of those
older rolls were likely unplayable, gone, or not favored anyway.

The conversions were very easy and took only a few hours.  Nothing
had to be done to the spools or tracker.  Only tubes were moved,
consolidated, tee'd together, and discontinued.  Wurlitzer's many
registers and percussion were still used, just combined.

Some adjustments had to be made chromatically, as the 165 scale used
four sections with many note compromises, while the APP / Caliola scale
was a chromatic piano scale in one section.  But Wurlitzer had worked
out a way to do that with compromise that an unsophisticated listener
couldn't really tell (or care about).

Newer 165 rolls were relegated to full-register monotony with constant
repeats.  The 165 organs with the many registers,  ranks of pipes,
and percussion options required constant maintenance and tuning.  The
APP / Caliola roll only had controls for two pipe registers: flutes and
violins and snare and bass drum.  The roll could operate the bells with
a complex duplex option that may not have even been used.

The APP / Caliola option eliminated all of those problems.  A simple,
inexpensive conversion solved all the problems.  Few knew or cared about
the pipes, registers, percussion, as it all sounded the same to most
anyway.  Suddenly, rolls, repairs, other maintenance, costs, were no
longer an issue in the final days of the larger organs and their music.
Operators had more inexpensive music played to unsophisticated customers
who didn't notice or care about the difference.

Wurlitzer's 165 and APP / Caliola roll production continued until 1945,
until Allen Herschell and then TRT Manufacturing Company took it over
and continued the same practice.

Fortunately, in the last decades, owners of the remaining converted
organs realized Wurlitzer's folly and had the organs returned to their
musical glory.  Contemporary arrangers now crank out music as creative
as Wurlitzer once did taking full advantage of the full, musical,
restored Wurlitzer 165 and 166 scale!

Glenn Thomas - Proud owner of two Wurlitzer 165 organs and continuing
to produce newly arranged Wurlitzer 165 rolls for today's appreciative
owners, audiences, and customers.
https://www.wurlitzer165.net/wurlitzer-165-rolls 
wurlitzer165@comcast.net.geentroep [delete ".geentroep" to reply]