Tanglewood performance at Koussevitzky Music Shed. Andris Nelsons leads the Boston Symphony Orchestra in a program pairing Mozart's elegant Piano Concerto No. 25 with Emanuel Ax as soloist, and Mahler's sweeping Symphony No. 4 featuring soprano Erin Morley. Tickets on sale beginning Thursday, March 5, 2026 at 10:00 AM EDT.