The green-paper Welte system was a development of the white-paper
one (which itself was a development of the red-paper system!) in about
1927.  It was not an improvement operationally but enabled a cheaper
instrument to give the same result.  The earlier systems used perfora-
tions in the edges of rolls for lock-and-cancel control features, while
the green system controlled the features directly from the roll.

Because of the late date of its introduction you will mainly find green
rolls in Germany and in Australia, where a big sales push was made
during the 1930s depression.  Bechstein had held aloof from player
systems until 1930, but then adopted the green Welte system in
desperation and sold a number of instruments in Australia, many of
which survive there.

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 | [] D   Dan Wilson (Friends of the Pianola Institute, London)
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