Table of Contents
Cobs
20-Note Cobs
- Played on the “Gem Roller Organ”, “Concert Roller Organ”, “Chautauqua Roller Organ”, “Home Music Box”, etc.
32-Note Cobs
- Played on the “Grand Roller Organ”
Alphabetic List
Numeric List
Tuning Scales
Roller Organs were not tuned to standard pitch, so there is great variation. A scale beginning on D will allow D, G, A, C, and E major chords and D, G, and A scales, so it is well-suited to play in the key of D or G. The mean temperament tuning1) allows it to play in almost perfect harmony.
1)
Mean temperament was used prior to 1908 (approximately). At that time the Autophone Company switched to equal temperament because the reed sets were slightly less expensive.
2)
most Gems after 1888, some Concerts after 1908
3)
most Concerts before 1908
4)
some Gems after 1908, some Concerts after 1908
5)
most Gems before 1888
