CLASSICAL MUSIC: Brendel Concerto Cycle, Barbican. Hagen Quartet Cycle, Wigmore Hall

Alfred Brendel's Beethoven piano concerto cycle at the Barbican climaxed last Friday to a supple account of the Emperor Concerto. Sir Neville Marriner and the Academy of St Martin in the Fields set the scene with a well-groomed opening tutti and Brendel responded with calculated flamboyance. The opening Allegro suggested tempered heroics, although the thunderous octave passage towards the movement's centre had considerable force. Brendel lunged at the keyboard, leapt back as if thrown by a sudden rush of current, then relaxed into characteristic repose. His response to modulation was as keen as ever, and never more so than in the slow movement, where his opening phrases flowed forth as on a single breath - delicately, meditatively and with a bel canto tone that even Horowitz might have envied. Marriner would glance across his shoulder, taking his cue from a dying cadence and erecting careful preparations for an ebullient though occasionally slap-happy finale.

A warm ovation prompted an exquisite encore in Beethoven's Bagatelle Op 126 No 1, a highly personal, even quixotic reading that made me long to hear Brendel play the whole set. Prior to the Concerto, Marriner had set Beethoven's Seventh Symphony on a dancing course where the timpanist Tristan Fry thrashed merry hell into the tempestuous finale. There were no repeats, and no affected mannerisms; just honest musical reportage, disciplined execution and a refreshing determination to let the music speak for itself.

Which posed the question: does Beethoven actually need much in the way of interpretative intervention? I suppose that depends on who's intervening, and if you attended the Wigmore Hall on Saturday night, you certainly won't have felt indifferent to what you heard. It was the Hagen Quartet's turn to present "Beethoven as a symbol of European Friendship" (the Carmina, Keller and Mosaiques Quartets are scheduled for early next year). Their journey shunted us back and forth from Beethoven's last quartet (Op 135), through the pensive "storm and stress" of his C minor (Op 18 No 4) to the celestial commentaries of his epic 14th in C sharp minor, Op 131.

The playing was breathtaking in its precision, dynamism and agility, with so much inflexional variety and quick-fire point-making that you constantly wanted to shout "hold on there - what was that you played? Let's hear it again!" To be honest, there was probably too much going on, though the sheer physical force of Op 135's scherzo - the manic trio in particular - exerted a circus-like fascination. Eccentricities were legion. The C minor Quartet's opening Allegro ma non tanto, for example, fired away at such a ridiculously fast tempo that pensiveness gave way to mild hysteria. As a "one off" it made for a thrilling encounter, but I'd not want to hear it again.

The scherzo was more extreme still, though when it came to Op 131, Beethoven steals the lead on all potential interpreters by parading so many outrageous ideas - one after the other, and with perennial unpredictability - that even the Hagens were brought to heel. Here they calmed to a more acceptable level of excitability and their performance was filled with subtlety and wonder.

Robert Cowan