The last time I reviewed Igor Levit in Limelight, back in the December 2014 issue, I wondered where a recording career that had begun with the late Beethoven Piano Sonatas and followed through with Bach’s complete Partitas might head next. “Levit is here to stay,” I mused; but in my wildest dreams I couldn’t have second-guessed this next move.

That said, if you are going to record Bach’s Goldberg Variations, then adding Beethoven’s obviously indebted Diabelli Variations makes sound historical and musical sense. But you can only imagine how the pitch to the suits at Sony, slowly digesting Levit’s proposal that they release what they’re assuming will be a hefty Bach/Beethoven pairing, unfolded. “And on disc 3…” “Disc 3, Igor?” “Yes, on disc 3, I want to record a 60-minute set of variations based on a Chilean song that preaches the values of Marxist revolution.”

Frederic Rzewski emerged during the mid-60s as a musical polymath: a free improviser who gorged on low-fi electronics in the collective Musica Elettronica Viva; a pianist who specialised in the likes of fingerbusting Stockhausen, Cardew and Boulez; and as a composer who, in works like The People United Will Never Be...