David Danzmayr returns to the SLSO with pleas for unity and progress from Felix Mendelssohn and James MacMillan. Mendelssohn’s radiant "Reformation" symphony culminates in a blazing hymn. Samuel Coleridge-Taylor was just 23 when he wrote his lush Ballade, a work pointing to great things. And soloist Conrad Tao shares Camille Saint-Saëns’ Piano Concerto No. 2, a work he calls “both charming and dramatic.”