Pierre-Laurent Aimard. Photo: Marco Borggreve/ Deutsche Grammophon.

It’s tempting to just say, go here, and read Anthony Tommasini’s New York Times review of the program played in New York on the 16th by pianists Pierre-Laurent Aimard and Tamara Stefanovich –the program they repeated in Carolina’s Memorial Hall March 18. Tommasini gives an excellent overview of the all-Boulez concert; however he says nothing about one of its most intriguing aspects.

The French pianist Aimard played at Carolina Performing Arts in November, 2012, giving an unforgettable concert featuring work by Claude Debussy. Afterwards, he mentioned to CPA director Emil Kang that he–with his former student Tamara Stefanovich–was working on a program that would include all of the piano music written by French modernist composer Pierre Boulez, with whom Aimard has long been close. Aimard was hoping to tour this somewhat daunting program in honor of Boulez’ forthcoming 90th birthday. Kang took up the challenge, making CPA the last of four stops on the US tour (Berkeley, Chicago, New York…Chapel Hill). Pierre Boulez will turn 90 next week.

One of the things that made this concert special was that the performers spoke (but not too much) about the works, giving them some context in musical history. The evening opened with Aimard playing Notations I-XII for piano, written by the 20-year-old Boulez at the end of WWII. They splinter and froth with complex emotions, a dozen new beginnings in 12-tone style from the wreckage of Europe. Aimard went on to play Boulez’ Sonata for Piano No. 1, from 1946, speaking beforehand of its “burning and icy sounds; its wild gestures, and the space floating or collapsing.” This, he said was “the music of a very young man who wants to make another French Revolution.” Certainly its spatial qualities are amazing, but more piercing are the extreme contrasts, which Aimard loads with color, from the bituminous tones of the lowest registers, to the nacreous pink high notes. Storming violet clouds shading toward bruised plum were pierced with fans of harsh viridian in the middle, the colors weaving together as the hands crisscrossed on the keyboard.

But then came the most illuminating aspect of the evening. One knows that each performer gives something different to the music, but here was a demonstration that would be hard to beat. Tamara Stefanovich took the stage to perform the Boulez Sonata for Piano No. 2, from 1948. It’s a much more advanced, complex work than the first sonata–she called it “monumental,” and “an acoustical tapestry that detonates in the finale”–but the extreme difference in coloration came from the performer. Stefanovich studied with Aimard; she played the same Steinway D–yet her palette was very different from Aimard’s. She’s very powerful, especially with her left hand, and stabbingly precise, though perhaps not as nuanced as Aimard, and much cooler. The undertones of her thundering low-register blacks, for instance, are blue and green, rather than golden.

One’s mind continued to explore this mystery of interpretation as the performers alternated again through the Cageian Sonata No. 3 (I thought I glimpsed the dancing ghost of Merce Cunningham), Incises, and Une page d’éphéméride. This last harks back to simplicity of the Notations, and the composer’s obvious delight in speed and risk seems more playful than destructive as it had in the Sonata No. 3.

Then, another Steinway was wheeled onstage, and the evening closed with Structures, deuxième livre, for two pianos, which allows the performers a measure of improvisatory freedom within the written score. They may take sections in different orders to make combinations that feel right at the moment. One plays, then signals to the other to respond–a musical poetry slam. You would have missed the fun of watching the challenging game, but if you’d closed your eyes, you would have been in no doubt of who was playing at any moment. Altogether, this was a most refreshing concert.