Jeffrey Kahane was such a forceful presence at L.A. Chamber Orchestra that it was likely a very difficult process to replace the conductor-pianist when he stepped down as music director in 2017 after a 20-year run. Jaime Martín has been designated as LACO's next music director. Although the Spanish conductor-flutist doesn't officially begin his position with the orchestra until next fall during the 2019-20 season, he presides over an interesting program this weekend. Mezzo-soprano Kelley O'Connor is featured in the West Coast premiere of Voy a Dormir, a song cycle that LACO co-commissioned from composer Bryce Dessner, who plays guitar with The National. The bill is buttressed with a performance of W.A. Mozart's momentous and moving Requiem.
Alex Theatre, 216 N. Brand Blvd., Glendale; Sat., April 27, 8 p.m.; $31-$143. (818) 243-2539. Also at Royce Hall, UCLA, 340 Royce Drive, Westwood; Sun., April 28, 7 p.m.; $28-$130. (310) 825-4401, laco.org.