Greetings!  Thanks to all who responded to my recent query concerning
the Normal/Soft operation on some late Duo-Arts.

The consensus seems to be that hole 94 on the tracker bar controlled the
key shift (una corda) pneumatic for soft playing during Normal play and
the hammer rail was lifted during Soft playing.  On some instruments
level 1 or 2 of the accordion pneumatic was also collapsed during Soft
play in order to "compensate for the lost motion".  I imagine that this
was done if it was found that the most softly played notes skipped when
the hammer rail was lifted.

Almost certainly I will not use this arrangement for two reasons.  First,
the large "L" shaped lever used to shift the action with the large
pneumatic is missing in my instrument.  I would have to make a
replacement in order to get it to work.

Second, I do not altogether like the idea of extensive use of the una
corda pedal because of uneven wear on the hammers.  At least initially,
I plan to tube the hammer rail lift to the soft hole in the tracker bar
and leave the Normal/Soft switch inoperative.

Thanks again MMD.

Regards

John Johns
Ottawa, Canada