In a year of concerts many will be good, many bad, and more will be somewhere in between. A couple will be great. Was anything more disappointing than Seiji Ozawa's correct, joyless Mahler with the Boston Phil? Was anything more extraordinary than Krystian Zimerman's Chopin?

Zimerman plays little. But he is great and he features, along with 73 other pianists, in one of the year's most remarkable recording projects: Great Pianists of the 20th Century. There are to be 100 volumes from Philips, and their edition is to be completed in time for the millennium. Other labels have contributed. Steinway is a sponsor and the pianists are all, or have all at one time been, Steinway artists. But this is no hobbling restriction.

"Why no Ravel and Debussy, Mr Schnabel?" the great German pianist was asked. "Because I am interested," he answered, "in music that is better than it can be performed." Schnabel respected the texts of great music. In an ideal world he might simply have contemplated Beethoven, rather than played him. Philips offers Schnabel playing Beethoven - two late sonatas - in versions never before released. There is the Waldstein and the Fourth Concerto, gentle and wise. Schnabel got so many encores for the Fourth at Carnegie Hall one night that he came out on stage wearing a Homburg hat and an overcoat, and only then got away.

Schnabel was interested, as few pianists these days are, not in particulars but in generalities, and sees the music whole. The Waldstein sonata's first subject rises from a throbbing harmonic glow; passages of gurgling semi-quavers blur into indistinctness to provide a backdrop against which the themes stand and deliver in loud relief; the slow movement retreats into monastic absorption. Schnabel dared, after long pondering, to be basic. But a Schnabel performance is on a knife-edge between pure magic and dry exegesis.

The volume devoted to Wilhelm Kempff contains a photograph of a small boy, hair closely smoothed, velvet bow flopping about the neck. Kempff is perhaps aged nine - the age at which, during his admission exam for the Berlin Hochschule, he proved able to transpose any one of Bach's 48 preludes and fugues into any key, by heart. Alfred Brendel, who has made the Kempff selections for the series, says that Kempff was among the most accomplished Liszt players of all. By extension, he was one of the greatest, tout court.

He was also a musician for whom cantabile "was the essence of music". A later picture dates from Kempff's heyday. The pianist is confident, relaxed, in cardigan and tie and with whitening hair. It is postwar; his Entnazifierung is over, and his enforced silence - "and perhaps even practising", says Brendel - has proved a boon. Kempff's playing from this period is beautiful and unstudied. In the vaporous C major intermezzo of Brahms' Op 76, with its slithering harmonies, it is also amused, elegant and dancing.

"We have been, let us say, to hear the latest Pole/Transmit the Preludes, through his hair and finger-tips." The electric silver hair, the aristocratic buttonhole, the aloof gaze of Artur Rubinstein seem meant for T S Eliot's effete image. But Rubinstein revolutionised Chopin playing: Eliot was writing about the generation of vapid players whom he superseded. The first volume devoted to the great Polish pianist - a romantic, but a hard-bitten one beneath the deluxe exterior - is a perfect recital: rainshowers of controlled embellishment meeting open-armed embrace of the most thundering challenges. No moonlight or dewdrops in sight.

There are other pianists we might choose to represent the century. Dinu Lipatti, Romanian of romantic legend, early death and gorgeous analytical gift. Arturo Benedetti Michelangeli, mysterious Italian who pretended Austrian parentage, about whom the French pianist Cortot exclaimed he was a "new Liszt". A simple phrase of a single repeated note in an easy Scarlatti sonata - in A major, K 322 - may be the most stunning thing in his volume: a delicate reproach to anything fancy and Lisztian.

And then there is Zim-erman: hyper-aesthetic, hyper-intellectual, hyper-refined, self-observing, video-monitored epitome of the modern, recording pianist. Could anybody else explode the fireworks of Debussy's Feux d'artifice with such savagery yet such grace? Could anyone rampage through Brahms, live, with Zimerman's combination of accuracy and insight? Leonard Bernstein's humane, over-personalised reading of Brahms' Second Concerto throws the pianist into a war of male power and tremulous female pleading that may be naive, or politically incorrect. But Zimerman acquiesces. And the result is some of the most extraordinary live playing on record.

Zimerman, trim and bearded, with a softly savage look to the eyes, has the Schnabel ability to see a piece whole, but he takes risks doing it. I would like, says Chopin in the score of his Fourth Ballade, a diminuendo on that note before the theme comes back, decorated. How does a note on the piano decrease in volume? By dying. To hear it die it must be allowed to linger. Zimerman leaves the note dangling twice, three times the length the composer specified. It is a temerity, and an interpretative freedom, which Schnabel could only envy.

This article first appeared in the 18 December 1998 issue of the New Statesman, A time for unadulterated tradition