In-Reply-To: Digest 98.05.22

Tim Baxter wondered whether there was a way of making notes 1-4 and
85-88 speak, using a specially-cut roll, on a Duo-Art piano.

I once saw this done for an Ampico for the top notes only. The trick
there was to tube a parallel pouch valve onto the reroll port and use
single punch reroll perforations on the roll which were too short to
trigger the reroll facility. A manual switch was used to tee into the
top three note tubes and steer the note appropriately, switching off
smartly when done ! You couldn't have long notes, but what difference
would it make there ? On the rolls I saw demonstrated, only one of
the notes was used on each roll, so selection was not a problem.

On a Duo-Art you could use the soft-pedal port instead. Automatic
selection could be devised by using a pneumatic version of the
teleprinter's mechanical Murray code decoder with a four-bit signal
on treble or bass theme port, choosing a moment when no note was
starting. Every snakebite would act as a start pulse and the decoder
would look for hole or no-hole in three very closely-spaced positions
following, giving a choice of 2 to the third power, 8, on each side,
allowing for four notes and four null choices. The null choices would
be chosen to match the most usual false operations from ordinary
"theming", such as start-0-0-0, start-0-0-1 or start-1-0-0. A roll
might still set up wrong choices in ordinary "theming" but it would
always be possible to cancel these with more snakebites before the
next soft pedal operation. Bass notes would have to be actuated on a
lock-and-cancel basis, like a Welte Licensee command. An interesting
project !

How many pieces of music use two simultaneous notes in either of
those ranges, though ? I can think of just one John Farrell roll
which does, a third at the top of the keyboard. The system would just
have to be allowed to fail - or use one of the redundant code
choices, or a simultaneous redundant code in treble and bass !

Dan Wilson, London