Someone (I apologise I have lost the name) mentioned 'Barzakh' by Brahem
Anvar which I think is great music--poignant and soulful in the best
meanings of those terms.  I had forgotten about it, and I just found it:
It is available on compact disk from Borders ($13.59 + s&h).

Although the original inquiry asked for choral or orchestral music, may I
add a suggestion that only marginally meets it? It is 'Mevlevi Ceremonial
Music' (Mevlevis are known in the west as whirling dervishes) performed by
the Mevlevi ensemble.  (Although there are many other recordings of that
music supposedly designed to please the western taste, this is the real
thing.) It is a collection of pieces played and sung in Mevlevi ceremonies.
I think it, too, is wonderful music, reaching the depths of one's soul.
(But anyone who is not familiar with that kind of music should give it a
chance by a second and/or third listening.  It will open up an astonishing
wealth of beauty.)

Peter Harzem