Overtones in old European Cathedrals Thoronet

The Cistercian Abbey Thoronet, the dark sister of Senanque, is sought out only by bats and other experts in echoes. Michael Vetter was inspired here to create two Songs of the Night: freely improvised liturgies, accompanied by tamboura, with expressive melodic development and several overtone passages to which the bats, crickets, etc., respond.