ROCK / Big brother Bob and the fabulous kid

TWO GREAT American singer-songwriters played in London this week - one whose reputation has been carved in marble for so long it could be mistaken for a gargoyle; another who's never been more than marginal, but whose gift for observation is in good order. The comparison between Bob Dylan and Loudon Wainwright III asks to be made so loudly it can only be done with a smile. Wainwright's song 'Talking New Bob Dylan' imagines a sense of community among those stuck in the great man's shadow. 'We still meet up every week at Bruce (Springsteen)'s house - well, he's got the biggest house.'

Trading up to the Royal Festival Hall after his sold-out autumn residency at the Borderline, Wainwright seems lost in space. His nervy movements, combined with the grotesque mid-song grimaces that are his self-deprecating staple, suggest a man in need of a public convenience. The show of unease is deceptive; he is a formidable entertainer. His eloquently parched voice, set off by nimble guitar or piano, and occasional supporting banjo and fiddle from Chaim Tannenbaum (Martin Amis's brother-in-law, trivia-fiends) and David Mansfield, is still going strong after two hours of fearless self-examination.

He opens with a new song about the Clinton inauguration, a hard look at his generation which concludes: 'hope we grow up before we get old'. Most of his songs are more personal, but awkward truths are his bread and butter. Therapy, marriage break- up, hitting children, going to the doctor's: it's not your regular good night out, but the lacerating wit which Wainwright brings to the trickiest subjects excuses the odd lapse into Iron John territory.

Bob Dylan, Wainwright's spiritual big brother, divides the generations like no one else. If you weren't old enough to be under his spell by Bob Dylan at Budokan, it was probably too late. His image as the embodiment of rock's highest aspirations - as seen in the absurd 'Which is better, Keats or Dylan?' debate (answer: The Jam) - has done nothing for popular music and not much for him.

For one who has long seen him as a malign force, it is worryingly easy to like him at the Hammersmith Apollo. Untrue to form, he delivers a fan-friendly mix of old favourites and new material. His singing, early on especially, sounds more like someone playing the comb - if you saw a man making this noise outside Sainsbury's, you might give him 50p, but only if he had a cute dog. But there is a certain, well, Bob Dylan-ness about him that is hard to resist.

Those back pages are treated with disregard; much-loved standards are brutally rearranged in in a bid to make the over-familiar unrecognisable. Was that 'Tangled up in Blue' or 'All Along the Watchtower', or both at the same time? The sober, cowboy-hatted band strive to curtail Bob's bizarrely off- key guitar excursions. His notorious harmonica, on the other hand, is perversely tuneful. By the end, the dread figure of Dave Stewart, loping on for 'Highway 61 Revisited', has spurred him into something like levity. He jigs about swapping ancient guitar lines, very nearly smiling. And then he does 'Ballad of a Thin Man', almost like he means it.

Loudon Wainwright: Bristol St George's (0272 230359) tonight; Cambridge Corn Exchange (0223 357851) Tues; Leeds City Varieties (0532 430808) Wed, Thurs.

(Photograph omitted)