Just picked up a copy of the Hilliard Ensemble/Jan Garbarek's second
collaboration, Mnemosyne (ECM New Series 1700/01, two CDs) at Borders.  If
you liked "Officium" you will more than likely like this one.  It contains
some Renaissance and Medieval settings (Brumel, Dufay, etc., sometimes with
interpolations and additions) as well as fragments of what are claimed to
be Quechua, Basque, Iroquois folk music.  ECM continues its excellent
tradition of cover/booklet art, this time borrowing images from Bergman's
The Seventh Seal (I thought I recognized that chess set!).  The title is
from a poem of Hoelderlin.  In a sea of New Age nonsense, this is the Real
Deal (IMO).

Strangely, whereas Officium was classed as "classical" this appeared in
the Jazz section of Borders.

Chris Bonds