Dear Colleagues, On an upcoming Helios Ensemble concert, I am planning
to perform some very early music. (Specifically, Hildegarde, Perotin and
Machaut, and Petrus de Cruce, among others). I have done some preliminary
research in the Univ. of N. Texas libraries, and have found some excellent
articles etc.I am in the dark, however, as to some technical questions
regarding editions etc.  I am aware of the Hildegarde Press, but I was
wondering if any of you who specialize in early music migh help me with a
couple of specific problems.

1. My knowledge of Hildegarde comes from hearing some fine recordings by

Sequentia and the Gothic Voices. There are instruments used in each
case. I have located a wealth of vocal music, but no instrumental parts.

I assume that these might be improvised or reconstructed.  Does anyone have
knowledge of published performance editions of this music that have

instrumental parts included, or at least some extensive essay on possible
performance options?

2.  Some of the library editions of the Machaut (Messe de Nostre Dame) and
the Perotin (Viderunt omnes) are rather old and not particularly easy to
read.  Can anyone suggest some recent performance editions of these works?

Thanks for your expertise!

Kevin Sutton