Wurlitzer Caliola Organ Pipe Dimensions
by Julie Porter (070407 MMDigest)

To Vic Searle and the MMD,  In reference to Vic Searle's inquiry as to the Caliola pipe scales: I made a comparison of a few Caliolas against the scale lengths in the booklet published by Doyle Lane.

The width and depths of the scales in the Doyle Lane pamphlet match those of the Caliolas I personally examined.  The lengths hand written onto these scales are too long when compared to actual pipes.   I made a spreadsheet of this data graphed against theoretical curves and sent this spreadsheet to the MMD editor for inclusion in the MMD Tech Archives.

The lengths written in the Lane pamphlet are about two inches over the lengths of the measured pipes.  It is not like the block height is the extra, but more like the pipes were measured as installed to the toe board.  The attached spreadsheet compares the Doyle Lane data against data from Tom Wilson and Bill Black.  This spreadsheet is formatted to be printed so I can see the dimensions in the shop with every other line having a nice gray background.  I made my Caliola pipes to this data.

I had problems with the top octave.  I was a bit heavy handed on the sander and the pipes came out with a rectangular cross section, so I remade them with a square section.  What does work is to cut the boards to the lengths printed in the Doyle lane data. If the blocks are made with a bit of extra length in the traditional way this extra length gets cut off and used as spacers at the top of the pipe during construction.

I made the extra about 5/8 inch or so.  By chance or design, when this clamping area is removed from the open end pipe, the finished pipe falls in line with the measured data.  Caliola pipes use slab tuners.  As built to these scales, there is about a full step in the tuning range.

Fritz Gellerman supplied copies of the original Caliola scale sticks to the MMD Archives.  These scale sticks show the Caliola is intended to play 1/2 step away from the notes indicated on the APP scale.  Bill Black provided me with the tubing of his Caliola which also confirms this shift in scale, where tracker note E plays the pipe marked F.

There is also some octave coupling to get the 65 notes of the APP scale to play the 44 pipes.  As the Caliola pipes start with F and the APP scale starts with A or A#, the first octave is only partly coupled at note A (or A#).

While no Caliolas with bells have ever been recorded from the factory, a study of these scales and actual "Caliola" rolls provides for the top octave to play the 12 notes on bell bars.  The APP scale, provides registers for two ranks of pipes, piano, drum, xylophone and bell bars.  This enabled Wurlitzer 165 and Wurlitzer 180 scaled organs to be converted to play "Caliola" rolls.

Julie Porter
07 Apr 2007 11:54:42 -0700

caliola01.xls  (79 kb, Excel spreadsheet)

See also the article about the Wurlitzer APP tracker bar scale and how APP rolls are played on the Caliola.


7 April 2007