Last year EMI released a recording by a musician it described as "arguably the greatest pianist in the world". The disc was "destined to become one of the greatest albums ever" and the record company's hype seemed, at the time, a good joke. On the evidence of a concert in London last week, EMI was underselling its artist criminally.
The same pianist played in Paris a fortnight ago and was greeted by the eminent music critic of Le Monde with a puff of stupefaction, an urbane shrug and a string of adjectives as long as the longest tier of an espaliered pear tree in the Jardin du Luxembourg (the same journalist being fortunate enough to hold the paper's occasional arboricultural brief). The impression of the recital, wrote Alain Lompech, was miraculous, marvellous, vibrant, stirring, dazzling. The actual playing he would, of course, forbear from describing. The pianist stood in no need of introduction from him: "On ne presente pas Martha Argerich."
In her mid-fifties a veteran of all manner of hyperbole, wearing a black Japanese silk dress, twisting her long black hair over her left shoulder as she prepared to set fingers to keyboard, the Argentinian pianist played Chopin's Piano Concerto in E Minor at the Barbican Centre. In the aftermath of such a performance what, indeed, can be said? That one retains a sense of raw activity and pure energy? That the entire concerto first movement, 20 minutes long, seemed a single fierce musical exhalation, propelled by one impulse? That the continuous agitation of the fingers seems, in retrospect, a mechanical impossibility?
Lompech remarked that hearing Argerich is as close as one gets these days to seeing Maria Callas, a performer whose very faults were virtues. But with Argerich there is no sense, as there may have been with Callas, of a performer living on the edge of failure. Technical breakdown seems inconceivable; the danger is rather an authentic musical one - the essential thrill of live music - that the performer might, on a whim, decide on a different performance altogether. It will still be Chopin. It will still be the First Concerto. But it will be Chopin as Martha Argerich wants him tonight, now. She will flip the next bar in any direction she cares.
Was it then surprising to hear such poetic playing? Only to those of us nurtured on an image of Argerich as a performing devil. True, in the concerto's finale she discarded the tempo set by her conductor, Emmanuel Krivine, and decided on a more congenial, faster one for herself. But on her new recording of the Chopin concertos with Charles Dutoit - released on EMI last month - she is obedient, less farouche. The mimicking of the cellos' pizzicato in the finale's central dance is with a pluck, not the pistol-shot snap of last week. The apotheosis of the slow movement's main theme is preceded by a snowfall of piano sonorities, not a windy gust.
At the same time as the concertos, EMI has released a Chopin recital recorded by Argerich in 1965. Suvi Raj Grubb, the producer, remembers the occasion: "I sat up in my chair with a long, drawn-out 'Jee-sus' - the balance engineer said 'Wow!'."
But Deutsche Grammophon had the right to issue the same repertoire before him, and EMI's has never been issued until now. The Argerich of 30 years ago is a technical marvel, a phenomenon, but angry and impetuous, raging into sudden fortissimos, unwilling to catch Chopin in his characteristic, ambivalent act of addressing a room full of people while playing to himself. For the full magic we must turn to the pianist of today.