I found Pete Knobloch's note in the 001023 MMD, "Player Music Roll
Brake Adjustments," all too true.  Everything he says about the
dynamics of the player system occurs also in the Wurlitzer band organ
transport system, in our case even down to the detail about someone
having oiled the brake pads.

I have noticed that slippage is usually triggered by a spot in the
music roll in the last or the next-to-last tune (depending a bit on
ambient air humidity) where no notes are playing  -- or very few are --
so that tracker bar suction on the paper is at its maximum.  That
slight additional resistance is enough to set the slippage cascade
into motion.

Of course the slippage is harmless and only a minor annoyance or
embarrassment, unless you happen to be recording the instrument when
it happens.  What I have sometimes done in that case is manually hold
back the roll for a couple of seconds between each of the tunes toward
the end of the roll to tighten the paper on the take-up spool without
interrupting any music.  Alternatively, I manually ease the pressure on
the brake during the last tune.  But one's hand gets pretty tired
holding the brake up for several minutes straight without bending it
or letting go of it.

Pete's theory that the cure is less brake pressure rather than more is
an interesting one, and I'm going to experiment with it next season.

Matthew Caulfield

 [ Maybe you could fit a brake to the feed spool shaft which would
 [ brake the shaft when the coin-trip slot passes over the tracker
 [ bar at the end of each song.  -- Robbie