by Operators Piano Co., Chicago.
Cremona made by Marquette Piano Co., Chicago.
Nelson-Wiggen with wood spool frame
Wurlitzer "Long Roll Frame"
Wurlitzer CX with 6-spool Wurlitzer Automatic Roll Changer that plays 5-tune A.P.P. rolls
Seeburg & Western Electric
Nickelodeon Spool Frame With Belt Drive -- by Ed Gloeggler (040528 MMDigest)
Round Belt Transmission Design -- by Robbie Rhodes