The pianist Igor Levit has shown an inclination toward big virtuoso repertory: Liszt, Bach, the late Beethoven sonatas. Nothing he has done, however, is comparable to this giant effort, comprising three ambitious and extremely difficult variation sets. The amount of preparation involved is mind-boggling in itself, and what's more, Levit has knitted the three works together with a common style that's extremely precise and unobscured by pedal. You could buy the set for the Beethoven "Diabelli Variations, Op. 120," alone, really; Levit offers a clean, probing reading that's not without a good deal of humor. The odd work out here is doubtless "The People United Will Never Be Defeated," a set of variations by American composer Frederic Rzewski on the Chilean folk song "El pueblo unido jamás será vencido." This work, despite its difficulties and despite (or perhaps because of) the fact that it has never quite fit the agendas of either modernists or neo-Romantics, has persisted for 40 years in the imaginations of players and audiences, and Levit makes a good case for its inclusion in the august environment in which he places it here. The works form a persuasive chain: Beethoven clearly knew Bach's variation set with its transfigured return to the theme at the end, and Rzewski's was explicitly modeled on Beethoven, with a big fugue at the end and a uniquely stretchy conception of the theme. Sony backs up Levit with crystal-clear studio sound, which was what was needed despite the pianist's Romantic virtuoso qualities. Strongly recommended.