This is a textless one, but you can use OOH and AH vowel sounds. Note that first time there is alto solo, and second time there are BOTH soprano AND alto singing!
This is the fourth song from Karl Jenkins and Adiemus's first album, Songs of Sanctuary, released in 1995.
Provided to YouTube by Warner Music Group Adiemus: Cantus insolitus · Adiemus Songs Of Sanctuary ℗ 1995 Jenkins Ratledge Ltd under exclusive licence to Parlophone Records Limited, a Warner...
Backing video to a live performance.
Album Songs Of Sanctuary.