I know next to nothing about Dzogchen and indeed the Nyingma in general.
My background is Gelugpa where the chanting I have encountered has been fairly flat or the deep throat chanting I can almost accomplish at times.
I have recently posted about receiving an empowerment form Dozgchen Rinpoche, in the course of which I received a mantra and also bought a CD of Dzogchen Monastery Chants.
I find the chants completely engrossing as they enter my mind, almost hypnotic, and chanting the one for which I have transmission is a wonderful experience.
The complexity of the Dzogchen chants seems to involve a lot of singing 'around' each syllable rather than simple enunciation, and some variation such as 'OYM' at the start rather than 'OM' or 'AUMN'.
Is this a characteristic?
Is it was intended to disguise the mantra, or because it is rooted in a more ancient form, etc ?
Here's an example:
http://www.youtube.com/watch?v=7YSlU1_kd-A

