Bärenreiter presents a new arrangement of Ludwig van Beethoven’s Mass in C major. While the vocal parts remain unchanged, the orchestra is replaced by four-hand piano and harmonium.

This arrangement, commissioned by the Harvard Choruses and the Massachusetts American Choral Directors Association from the composer, conductor and musicologist Michael Ostrzyga, continues the tradition of arranging large-scale works for four-hand piano—a practice that reached its peak in the 19th century.

In i...