While I see suggestions that there are more than one manufacturer for 30-note music boxes, I see no evidence of that. All the photos from different suppliers seem to show exactly the same design – not even small changes that could be expected from a single manufacturer as they make slight changes over the years.
All the verifiable information I have seen seems to speak only of a music box tuned to the key of F, even though the paper strips all seem to be notated in the key of C, with the weird labelling of # notes. (For example, F# is written #F, which is confusing, since one might incorrectly assume that the # actually refers to the note before it.)
All of the comments about music boxes being different seem to be attributable to these two anomallies, and the resulting confusion.
1) Does anyone have any evidence that there are different manufacturers and not just many resellers?
2) Does anyone have any evidence that there are 30-note music boxes that are not in the key of F?
We are using the music boxes in live music performances of original music combining the music box with voice. While it is still possible sometimes to play some melodies in some adjacent keys, the existence of music boxes in other keys would enlarge our repertory possibilities.