After the new-music intensity of the Biennial and the rigor of the Beethoven piano concertos, the Philharmonic lightens up with this popular series, directed and narrated by Bramwell Tovey. The rising pianist Joyce Yang stars in these all-Russian evenings, performing Rachmaninoff's luscious "Piano Concerto No. 1" in a program that also includes Shostakovich's Festive Overture, Tchaikovsky's "Waltz of the Flowers" and "Marche Slave," Rachmaninoff's "Vocalise" and Mussorgsky's "Night on Bald Mountain."