If you are like me and have been looking for St. Hildegard's music online (not just recordings), you've probably run into some of the same problems I have. There are only a few transcriptions available online, and those transcriptions represent only a couple of Hildegard's works. Most of those transcriptions are in modern notation which for me goes one step too far. The Riesencodex is also available online, but it uses older neumes that require some knowledge to read. Sequentia (musical group) has done many recordings of Hildegard's music which are respectable.
I have decided to create a project which will make transcriptions of Hildegard's music available in modern Gregorian neumes (using gregorio). The project is located
here on google code where anyone interested is welcome to contribute (especially if you are some kind of expert, which I am not).
To give you some idea, here is the Riesencodex Manuscript of "O Vis Eternitatis"
I listened to Sequentia to hear how they interpret the neumes. I am guessing they are using a different manuscript because there are a few places where, if that isn't the case, they have employed artistic license. Most important among these discrepancies are the places where we see the leap of a fourth or fifth above the staff, Sequentia is heard to be singing a minor third - which is not musically unpleasant and possibly is written that way in a different manuscript.
I read a blog post on different possible interpretations of the different manuscripts, but to make my life simpler, I have decided to avoid exegetical questions between the Dendermonde and Riesencodex to produce something that is as faithful as possible (
update: I found a guide to reading the neumes here and as a consequence will need to rework a little the O Vis Eternitatis) to the Riesencodex:
