What maestro active in New York has expanded our symphonic and operatic horizons a fraction as much as the scholar-maestro Leon Botstein, president of Bard College and music director of the American Symphony Orchestra? In a word, none. Botstein’s latest program acquaints us, for starters, with the 1849 Stabat Mater of Peter Cornelius. If that name rings a bell, it’s for his comic opera Der Barber von Bagdad, a work cited once in a blue moon, perhaps for the curiosity value of the title (a full-length recording on Spotify, dated 2008, has clocked 2,139 plays of the overture, none for any remaining track). Who knew that there’s also a substantial catalogue of sacred music by Cornelius? His Stabat Mater, heard here in its U.S. premiere, is advertised as “a score of stunning originality,” remarkable for “its bold harmonic language, unusual formal design, and dramatic flair.” Luigi Cherubini’s Requiem in C Minor (1816), which commemorates the execution of Louis XVI in 1793, was known to and admired by composers including Beethoven, Schumann, and Brahms. Too, it has had champions in such lions of the podium as Arturo Toscanini and Riccardo Muti. Yet performances remain rare. The American Symphony Orchestra’s season announcement emphasizes the somber tone of Cherubini’s setting, along with its “astonishing” orchestral effects and “tender moments of reflective beauty.” —Matthew Gurewitsch