Question: What was the name of the period instrument ensemble that was formed in the 1950s by the conductor with whom Elisabeth Kulman recorded Beethoven's "Missa solemnis"?
Sentence (from "Nikolaus Harnoncourt"): Starting out as a classical cellist, he founded his own period instrument ensemble, Concentus Musicus Wien, in the 1950s, and became a pioneer of the Early Music movement.
Relevant evidence: Yes