Thanks to Nakun for this link.
BIG OM OF TIBET: Om chants, prayers and mantras
Recorded in monasteries in the Himalayas, this CD transports the listener to real life ceremonies in the actual monasteries and nunneries--not some studio. Traditional chants of Yamantaka, Mahakala, 1000 Buddhas, Offering the Mandala and others. recording by Stefan Ackermann