Are APP rolls and Caliola rolls really different?
I received an email inquiry today concerning Wurlitzer APP (Automatic
Player Piano) and Caliola rolls, which made me think about the supposed
difference between the two roll styles. They both use the same scale
and the same hole assignments. So APP rolls can be played on a Caliola
(organ with wood or metal pipes) and, I suppose, vice versa.
I'm told that there is a difference between the two types of rolls,
based on the fact that a pipe sounds at uniform volume from the moment
is it turned on until it is turned off, while a piano string, once
struck, continues to "sing," albeit with decaying volume, after the
hammer is released, until the damper mutes it. Therefore Wurlitzer
supposedly used extended perforations in its Caliola rolls as compared
with the shorter perforations in their APP rolls.
Has anyone compared the same tune on an APP and on a Caliola roll to
see if this is, in fact, true? Wouldn't the APP roll require equally
long perforations to keep the dampers suspended? Or am I missing
Is this perhaps a refinement that the company practiced in its early
days but ceased to bother with in the ember days of the roll business?