Source of music not stated at all, I can't for the life of me find a copy of the document mentioned above anywhere, it's not in the digital library of the BNF, nor in Archives.org or google books either. It doesn't sound medieval anyway. Troubadours' music: ~10% of the whole bunch of songs were collected with their music.
The way the lyrics are noted is a much later transcription too -. Most of the foreword is about the Provençal spelling (almost 150 years later... still accurate! -sigh!)