The award-winning Ehnes Quartet (James Ehnes, violin; Che-Yen Chen, viola; Edward Arron, cello; and Mercer's director of the Robert McDuffie Center for Strings, Amy Schwartz Moretti, violin) closes the 22-23 Fabian Concert Series with a rousing finale featuring the music of Haydn, Bartok, and Mendelssohn for recognizable works that will send off the series with…