Actually, I haven't created this instrument because I was in need of a new music box sample library. I just saw a guy on YouTube composing whole songs for real boxes, and I felt the urge to record one on my own. The music box was tuned in C-major so I pitched certain samples to fill the gaps and to obtain a chromatic playable instrument. For the recording of the samples I used an AKG C214.
While I played around with the samples I started to create different sound design patches and I ended up, adding four of them to the main library. To keep things simple and straightforward I built a second patch for them and added various effects to control and enhance the sound. Watch this video to get an overview over the patches.
You can download the instrument here. To use it you need the full version of Native Instruments Kontakt, at least version 5.8.1 (I can't guarantee that it is running on earlier versions). All public redistribution of the library or the samples used to create it is prohibited.