Stefan Schmidt improvises on the great symphonic 3-59 Göckel organ in St. Peter’s, Düsseldorf on Gregorian Chant tunes for Advent and Christmas as sung by the Schola Ars Cantandi directed by Peter Petermann. Conditor alme siderum Rorate coeli Ave Maria Ecce virgo Puer natus est Alleluia Viderunt omnes Ecce advenit Reges Tharsis Vidimus stellam Christe, redemptor omnium