Both those albums seem to be employing "Ars Antiqua" in its looser sense -- 'old music' being anything before the 18th century, apparently. Heinrich Biber was a 17th century composer.
The problem is, "old" keeps changing. We are anxiously awaiting the day when "On Eagles Wings" and "Here I Am Lord" become 'old music', never to be seen again ever. But I bet by 2075 somebody will be doing a centennial revival.
11 posted on 10/21/2010 7:31:46 PM PDT by AnAmericanMother
(Ministrix of ye Chasse, TTGC Ladies' Auxiliary (recess appointment))