Jasonl:The "Knoebels" sounds like a good place for band organ fans.There is a person I know in the Wash DC area that has a collection of band organs and juke boxes-sold many of them off years ago-went thru his warehouse-asked him if some of his organs played-didn't say a thing-just turned it on and started it up-MUSIC.He also owned the carousel on the Mall in Wash DC-the one across from the Smithsonian.The programs are "loaded" into the organs-In American models such as Wurlitzer-they are on rolls much like a player piano.They play by vacuum.European instruments use a perforated "folding music book"-or card system reed like feelers sense the holes in the book card and then sound the corresponding instrument.-just like the Jacquard weaving loom.the cards for those are still used by some weaving companies today.Very durable and relaible system.Remember the harsh outdoor conditions band organs may be asked to operate in-damp or dry outdoors.also the book organs may use a "pressure" system-opposite of the USA organ or piano "Vacuum" system-a puff of air goes thru the book hole-causing an instrument to play.A pinch roller holds the book against the tracker bar.At Glen Echo-the organ operator there told me he got most of the 165 rolls from a local yard sale-the rolls were marked "Misc Piano" rolls-they were a roll library for a 165 organ-he bought them on sight-paid something like $10 for them.He also cuts rolls himself-he has "arranged" some interesting songs-like the "Candy Man".Once you know the tracker system of the organ and musically inclined-you can play the organ by "programming" it with your own cut rolls.Its a tedious process.He cuts them by hand.Roll makers cut them by machines.The machine may be programmed by a computer-Apple ones work good for the process."QRS" roll company still makes rolls for pianos and organs.The instrument you saw and heard that was a piano with percussion is an " Orchestron"Yes they were the precurser to the jukebox.They had either a piano or an organ as the foundation instrument.Many companies built them before the jukebox took over.There are many folks who collect and restore these devices.Still interesting today. In fact many young people when they seee and hear a band organ ask-"Where can I get one of these?Is this something new?"You then explain to them that the instrument playing could be almost 100 years old.