This week's program features Heinrich Biber's monumental 53-voice Missa Salisburgensis, plus a sample from a new release of his Mystery Sonatas.

• Heinrich Biber: The Ascension from the Mystery Sonatas. Featuring violinist Christina Day Martinson and members of Boston Baroque. 
• Heinrich Biber: Missa Salisburgensis a 53. Performed by The Gabrieli Consort and Players, directed by Paul McCreesh, and Musica Antiqua Köln, directed by Reinhard Goebel.