MUSIC / The legend lives on: Nick Kimberley reviews Rostropovich, and Joan Rodgers

It's difficult to pin down what it is that makes for a forceful stage personality. Flamboyance and charisma are not synonymous, as Mstislav Rostropovich proved before a full house at London's Barbican last Saturday. On stage, Rostropovich seems tiny, barely able to wrap himself around his cello. As he plays, he stares into the air, or looks nervously over his shoulder at his accompanist (here, a confident Ian Brown). Nothing suggests charisma, and yet his rapt self-absorption held the audience in the palm of his hand.

History is part of his secret. Rostropovich is a living legend, and not only because some of the century's greatest composers - Shostakovich, Prokofiev, Britten - wrote pieces for him. As he plays, we feel a living tradition that stretches back to the heart of Romanticism, for Rostropovich was taught by his father, who in turn was taught by his father. His playing gains much of its authority from this sense of a tradition.

His performance of the fifth of Bach's solo cello suites proved the point. Not for Rostropovich the crisp articulations and vibrato-free zones of the period instrument movement. Here, the dance rhythms which thread their way through the piece sometimes sounded flat-footed, and Rostropovich's intonation was sometimes irregular, spectacularly so on one or two occasions. Yet the performance was whole, and not without its own sense of the modern: in these hands, the opening prelude might be Shostakovich looking deep into the empty heart of this century. Perhaps that's why the dances trod so heavily; dance need not be frivolous.

For all the power of the performance, the Bach seemed always on the verge of eluding Rostropovich. His authority was unquestionable in Prokofiev's sonata for cello and piano, written for Rostropovich in 1949. Here the rhythms were properly flexible as Rostropovich led us and his pianist through the work's changing mood, so skittish as to be dizzying. This was the show's centrepiece, overshadowing the Bach and Beethoven's Mozart variations which had preceded it. The Rachmaninov Vocalise which followed seemed drunk on its own lyricism, and we in turn became intoxicated. Then, like an encore before the real encores (Ravel, Stravinsky), Rostropovich performed his own Humoresque, written in 1945. This extrovert party piece requires superb technique to keep its galloping cascades of notes in control, and Rostropovich pulled it off with panache. The audience's enthusiasm was unbounded. Rostropovich himself looked slightly bemused, but that's charisma for you.

Two days earlier, in London's Wigmore Hall, Joan Rodgers proved that you can perform Berg and Schoenberg in the same programme, and still get a capacity audience and generous applause. Yet this was an oddly characterless performance from a soprano who has proved time and again on the opera stage that she has plenty of personality. After a nervous start, the voice proved to be in good shape and the hands expressive, as if simultaneously shaping the music and pleading with her listeners. Something, though, was missing.

Too often the boldness of the voice became crude and over-emphatic, particularly damaging in the six Strauss songs which she performed. Forcefulness became a cover for a certain lack of character. Occasionally syllables failed to emerge, or were given insufficient weight. And just when the songs demanded a bright, forceful personality - as in Schoenberg's Brettl Lieder (Cabaret Songs), Rodgers became pert and coy. Her accompanist, Roger Vignoles, was attentive, but neither he nor Rodgers quite managed to stamp their identity on the evening. Only charisma can do that.