O Rex gloriae (O King of glory) is the antiphon to the Magnificat for Second Vespers at Ascension. Byrd’s setting of the antiphon was published in the 1607 Gradualia it’s a five-part (AATTB) setting which demands considerable vocal range and dexterity from those singing it. Enjoy :-).
William Byrd (±1539-1623): O Rex gloriae
O Rex gloriae, Domine virtutum,
O King of glory, Lord of all power,
Performers: The Cardinall’s Musick conducted by Andrew Carwood