Tom Grace asked a couple of questions concerning 165-to-Caliola
conversion that had never occurred to me, so I got on the phone to Max
Hurley, operator of the Glen Echo Park 1926 Dentzel carousel, which has
the band organ in question, to see what he knows about it.  Max says
that it was a factory coversion done in the late 1940's or early 1950's.
If that is the right time frame, it must have been done by T.R.T.  rather
than Wurlitzer, because Wurlitzer sold its band organ business in
1946 -- unless for some reason Wurlitzer continued to do conversions
after 1946?

The tracker bars still in use on the band organ, even though it now
plays 165 rolls, are Caliola bars, as can be seen by the positioning
of the offset bass and snare drum holes.  On a 165 tracker bar the
offset drum holes are holes 11 and 67.  On the Caliola tracker bar
they are holes 6 and 74. (By "offset," I mean they are displaced
upwards a bit from the horizontal line on which all other holes lie;
in addition they are bored as slightly larger round holes, in contrast
to the smaller and rectangular holes that comprise the remainder of the
bar.  For accuracy's sake I should add that the 165 bar has the castanet
hole also offset in the same way; but that is not germane here.)  Even
though the offsets are now wrong for the organ, it seems to make no
difference in its effect, bringing into question the necessity for the
offsetting in the first place, especially when the organ is playing
recuts of original rolls, with their inherent lack of precision.

I don't know how whoever did the conversion got around the lack of
chromatic pipe ranks in the organ.  As Tom says, the Caliola scale is
completely chromatic.  Max said that Durward Center had to make some
new pipes when converting back to 165 from Caliola, because some of the
pipes were rotted from lack of use, and because at least one bass pipe
had been shortened to play Caliola.  Max also believes that some of the
pipes were re-tuned to supply needed notes.  Since the Caliola roll has
no registers and the 165 has many, including 4 separate melody registers
playing 8 melody ranks, there would have been some spare pipes, but no
way to blow them separately that I can see.

I don't suppose Durward Center made any notes on how the organ was
tubed before he disassembled it for restoration to original condition.
But he may be able to give some clues as to how the Caliola conversion
was done to avoid dead spaces in the music.  I have some old tapes of
the organ playing Caliola rolls, and it does wheeze, but that is due
to bad maintenance rather than to defects in the conversion itself,
I think.

As to the question why anyone would convert an organ made for 165 rolls
to the Caliola system, I think that the answer is that more -- and
perhaps better -- tunes were available on Caliola rolls than on 165
rolls in the 1940's and later.  Caliola arrangements and APP
arrangements were pretty interchangeable, so the combined market was
bigger than the 165 market.

Ok, even as I write this I can't quite convince myself that this was
the reason conversion was done.  But it has always been alleged that
"Caliola rolls were more available than 165 rolls after the war."  It
would be interesting to tally the number of APP/Caliola masters up in
the Herschell Carrousel Factory Museum today and compare that with the
number of 165 masters there.

Alan Bies' Wurlitzer 180 was factory converted to play Caliola because
of the extreme shortage (and expense) of 180 rolls.  I know of only 9
surviving style 180 rolls.  There were never very many made, and they
were short (8 tunes per roll rather than 10) and expensive ($50 per
roll in 1933, when 165 rolls were selling for $35, according to Ron
Bopp's "The American Carousel Organ," p. 246).  Production of 180 rolls
must have stopped before the end of the '30's.  So there was good
reason to convert a style 180 band organ.  But admittedly no comparable
crisis existed for 165 rolls: though quality and quantity dropped,
production never stopped.  So the conversion doesn't make a lot of
sense to me; but it did to somebody.

Not a very good answer to any of your VERY good questions, Tom, and
I'll sure look for better ones now that you've made me think afresh.

Matthew Caulfield