As evidenced by the rectangular box with five knobs, the unusual player
mechanism in the Kimball piano is a type of Recordo system.

As Art Reblitz mentions in his book, "Player Piano Servicing &
Rebuilding," (paraphrasing) there were many companies that made player
pianos that could play Recordo rolls.  Most of those companies designed
and built their own expression mechanism.

At Player-Care there are several references that cover a number of
Recordo systems.  Over the years, I've found that having all of them at
my disposal makes the job of getting every system working correctly
much easier.

	https://www.buysecure.com/playercare/reprints.html#recordo 

Musically,
John A. Tuttle
Player-Care.com
Brick, NJ, USA