If you reject the strictly chronological approach as too didactic, there are countless other ways of arranging Beethoven's 32 piano sonatas into a satisfying series of recitals. Daniel Barenboim's eight programmes at the Festival Hall distribute the highlights evenly, but the series began at the beginning, with the F minor Sonata Op 2 No 1, and it will end with the last sonata, the C minor Op 111.

For those of us who grew up with Barenboim's first recordings of the Beethoven sonatas in the late 1960s, hearing him return to these works 40 years later is a strange experience.

There is inevitably something more considered about his playing now, perhaps an awareness that he is one of the last heirs to the performing tradition that shaped music-making through much of the 20th century. Here Op 2 no 1 was presented not so much as Beethoven freeing himself from the constraints of classicism as lighting the fuse for the expressive explosion that would soon arrive with Romanticism, though Barenboim kept everything in scale, conjuring up intimacy even in the Festival Hall.

Never one to duck a challenge, Barenboim ended this first recital with the biggest test of all, the Hammerklavier Sonata Op 106. That was less successful, not because it lacked great moments - the hymn-like presentation of the slow-movement theme was glorious - but because it seemed to be parcelled up into manageable portions, and the sense of a dramatic vision welding its anarchic elements into a blazing unity was not quite there.

· Barenboim plays Beethoven's piano sonata cycle until February 17. Box office: 0871 663 2500.