I first heard Maria Callas as Rossini's Armida at the 1952 Maggio Musicale. And in Opera I wrote: 'This American-born Greek soprano deserves fully the considerable reputation that she has won, for she must be one of the most exciting singers on the stage today. Her presence is imperious, her coloratura not piping and pretty but powerful and dramatic. It must be noted that a nasty edge crept into the tone from time to time; but when she sailed up a two-octave chromatic scale and cascaded down again (in "D'amore il dolce impero") the effect was electrifying...But when tenderness and sensuous charm were required, she was less moving. This seems to be her present limitation; it may well disappear quite soon.'

At the time I didn't know she had learned that glittering role in five days. Then, in August the same year, in the Verona Arena, I heard her Violetta: dazzling in the first act, thereafter tender, poignant and passionate. I remember how, flinching beneath Alfredo's insults, she seemed physically to shrink. In a 1961 interview she recalled Tullio Serafin saying to her: 'You want to know how to act the opera? You have only to listen to the music.' Then added, 'I felt I knew exactly what he meant, and that is perhaps my biggest secret.'

Three months later Callas came to Covent Garden for the first time, as Norma, the role that Lilli Lehmann thought more demanding than Isolde, and that Callas called 'the most difficult in my repertory'. Between 1948 and 1965 she sang it 90 times, in eight countries. She recorded it twice (1954 and 1960), and several live performances have also survived. Norma was her debut role not only at Covent Garden, but also in Mexico City (1950), Chicago (1953) and the Met (1956). She sang it again at the ROH in 1957.

Since critics recalling great singers of their youth are often charged by their juniors with revisiting performances through rose-tinted ears, let me write not from memory at all, but by quoting directly what I wrote about that 1952 Norma at the time:

'Maria Callas is, surely, the most exciting singer on the stage today. Her virtues? Great range and power, prime necessities. The ability to invest coloratura with dramatic and expressive qualities (needed by all heroines of serious opera so far as the middle Verdi). A great range of vocal colours, allied to an exceptional dramatic understanding. Tones that are affecting, and tones that are thrilling. An imposing presence, gesture and physical expression, command of the stage rarely found today in any actress. In sum, Callas is a star. [I specified some unforgettable phrases, then added] To be sure, there were moments when the tone became less beautiful. They were flecks on a superb assumption.'

I stand by that still. Recordings are the evidence - of all but the incandescent physical presence. Photographs catch something of it, but the only extended video of Callas on stage, Act 2 of the Covent Garden Tosca, focused on whoever was singing, so the intentness with which she listened is lost. To bolster my youthful - and undiminished - enthusiasm, let me add the considered verdict of the mature critic who in Gramophone's Quarterly Retrospect judged singers by the highest vocal standards over 22 years. And he had heard Rosa Ponselle's Norma. Writing about Callas in New Grove, Desmond Shawe-Taylor took into account, as I had, the cavils inequality between registers, occasional harshness, some unsteady high notes - but then he declared:

'Of Callas's artistic pre-eminence there can be no doubt. Among her contemporaries she had the deepest comprehension of the classical Italian style, the most musical instincts and the most intelligent approach, together with exceptional dramatic powers. Her first appearance on a stage aroused immediate excitement...There was authority in all that she did, and in every phrase that she uttered...Her technical defects were far outweighed by genius.'

She was only 23 when she came to the world's attention with the Verona Gioconda in 1947. She turned 24 just before her Isolde and Turandot at La Fenice. The Walküre Brünnhilde and Kundry were added in 1949, and Turandots and Isoldes throughout Italy dominate the early Callas annals. Many reasons - slimming, unhappiness, ambition, Walter Legge's determination to see her Angel recordings outsoar Tebaldi's Decca sets - have been adduced to explain the vocal troubles that later afflicted her astounding voice, when her blazing artistic ambition and integrity failed to find their perfect vocal fulfilment. The youthful, unstinted outpouring in heavy roles seems to me the most likely reason.

Serafin should bear some of the blame, perhaps, though he was also an important ingredient in her greatness. He cherished and coached Callas, as he had Rosa Ponselle, whose first Norma he had conducted in 1927, and as he later cherished and coached Joan Sutherland to her Lucia triumph in 1959. Serafin worked with Callas on 17 roles, recording nine of them with her - indeed, Lucia and Norma twice over. He was one of the last conductors to understand how tradition could inspire individuality to its fullest flowering. He had worked with Muzio and Rethberg, besides Ponselle. Callas, as we can hear on record, inspired and flowered under great conductors: Serafin, Gui, de Sabata, Karajan, Giulini, Bernstein. But it was under Serafin - so often the young Callas's mentor, partner and collaborator - that she, while still in her twenties, generously and gloriously poured out vocal capital into many an Isolde, Turandot, Brünnhilde and Kundry. Few of her Wagner recordings survive: a couple of Liebestods, a poorly recorded pirate Parsifal. (Where were Wieland and Wolfgang Wagner's ears and eyes, that they didn't engage her for Bayreuth?)

She dropped Wagner, moved into a repertory that included some 'classical' heroines (Gluck's Alceste and Iphigénie en Tauride, Cherubini's Medea, Spontini's Julia in Vestale); operas by Rossini, Bellini, and Donizetti; much Verdi; some Puccini. And other things, of course. Among the odder excursions were Salome in Stradella's oratorio San Giovanni Battista (1949) and - her only 'creation ' - Euridice in Haydn 's Orfeo, which had its world premiere in Florence in 1951. In the studio, though never on stage, she sang Mimì, Manon Lescaut, Nedda in Pagliacci, and Carmen. Of Mozart, she sang only Konstanze, in a Scala Entführung in 1952. In 1955 Bing offered her the Queen of Night at the Met, but the piece was being done in English, and she turned it down. She recorded arias of the Countess, Elvira and Anna. In a Juilliard class, she said: 'Mozart should be sung with the same frankness you sing Trovatore with – but in a Mozart style.'

Verdi loomed large. For EMI, often with Serafin, she recorded Rigoletto (which she sang onstage only twice, in Mexico City, 1952), Trovatore, Traviata, Un ballo, Forza and Aida. In addition, a 1952 live performance of Macbeth at La Scala (surprisingly, her only Lady Macbeth) has been officially released; and, unofficially, her only Nabucco (Naples, 1949), and I vespri siciliani from the 1951 Florence Maggio. In all, she utters and weights the words and carries sound-cum-sense in every phrase.

That can be said of all she did. Perhaps her greatest mark on musical history was made by persuading people to take seriously the serious operas of Donizetti and Bellini. In 1925, Lucia had been laughed off the Covent Garden stage after a single performance, as ridiculous old rubbish. Callas, by her performances in Lucia, Anna Bolena and Poliuto, in Norma and I puritani and Il pirata, fired the bel canto revival. Karajan took part in it. Of the 1955 Berlin Lucia, John Ardoin says, 'If I could own but a single Callas set, it would be this one.'

In the words of Grove, 'her fame reached a level that recalled the palmy days of Caruso and Chaliapin.' I heard her often, met her just a few times, and only once not in company. One afternoon long ago - in 1959, when she was in London for Medea - she came to tea and told me about, enacting in outline as she spoke, the new Zeffirelli production of Traviata she had sung in Dallas (just two performances, which proved to be her last of the role that, after Norma, she sang the most often). But it's my memories of Callas in the theatre that matter to me more.

Books about Callas would fill a big bookshelf, and still they appear. I find two useful: Henry Wisneski's careful Maria Callas: The Art behind the Legend (Doubleday: 1975), with its rich iconography and Arthur Germond's detailed performance annals; and John Ardoin's The Callas Legacy (Duckworth: fourth edition 1995), which guides us acutely and sensitively through the maze of Callas recordings, official and pirate: from the putative 'Un bel dl' of 1935, when she was 11, to her work on 'Ah! perfido' in 1976, and in 1977, just weeks before her death, on Leonora's phrase in Forza, 'Deh, non m'abbandonar', as she sought to discover whether her voice might still serve her. That phrase finds her, Ardoin says, 'in very solid, easy voice'.

Callas the woman has been the subject of much journalistic speculation. It is Callas the artist who matters here, and her achievements are inscribed in sound for all to hear. In these pages, long ago, I tried to define what had been gained, what lost, when she re-recorded her famous roles. A summary might be: 'She gave musical expression to the words.' At the close of her Juilliard masterclasses she urged her students: 'Keep on going, and in the proper way: not with fireworks, not with easy applause, but with expression of the words and with real feeling.' In Tito Gobbi's words, 'She was like a vivid flame.'

This article originally appeared in the December 2000 issue of Gramophone. To find out more about subscribing to Gramophone, please visit: https: gramophone.co.uk/subscribe

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