[ Ref. 180615 MMD, 1914 Steinway Upright with Welte Changer ]

With a bit of detective work, I found that Welte called their roll
changers the "Welte Musicalle".   I believe the term "Multi-control"
may have been the name bestowed on the device by the manufacturer,
Automatic Musical Instrument Company of Grand Rapids, Michigan

  https://mtr.arcade-museum.com/MTR-1928-87-17/07/ 
  https://mtr.arcade-museum.com/MTR-1928-87-2-SECTION-1/19/ 
  https://mtr.arcade-museum.com/MTR-1928-87-19-SECTION-1/01/ 

Dave Krall
Hammond, Indiana