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Bridging
By Karl Petersen

About 1971 the Player Piano Co. came out with a series of Ampico recuts
which had unusual bridging (and came in beautiful, heavyweight boxes).
These otherwise looked like Powell rolls punched by Malone. At the next
So.Cal. Amica meeting, Powell made his (only?) appearance to let the
assemblage know that these rolls were made on Powell's own equipment
and should not be purchased. Powell was doubted because of the
difference in the chaining, but he said that the electronic chain
generator could be set to make the leading punch and the chain punch
any length, independently.

Shortly later, George Coade was hoping to clean up the punching method
he was using for duplicating, I think, Philips Paganini rolls, and I
designed a mechanical chaining escapement to go in the punch control
line. It would skip two, punch six holes continuously then skip 2,
punch 1, skip 2, punch 1, and so on until the control was released,
then punch one to finish. The initial skip 2 made up for the final
punch 2. This was a rotary ratchet device inspired by a ball point pen
actuator.  Unfortunately, only one prototype was built and I lost
contact before George got a look at it.

With Wayne Stahnke's remastering, you actually know where the music
events are on the roll, and, it seems to me, you could adjust the
chaining to optimize roll strength. I have not seen any instrument on
which the extended notes do anything other than sustain. I did post a
discussion about controlling the intensity by the length of the leading
perforation, though, and still have the hardware to demonstrate that.

OK, Karl B. Ellison, tag, you're it!

Karl A. Petersen¶
kap@firedragon.com

(Message sent Mon, 28 Oct 1996 06:02:31 -0700 (MST) , from time zone -0700.)

Key Words in Subject:  Bridging