My Massive Attack Meltdown

'I wouldn't wish a Massive Attack Meltdown on anyone', quips the drummer from Fleet Foxes, a charming and endearing band with a tendency to hide behind their considerable volume of hair. 'It sounds like a terrible psychiatric disorder'. Judging by the evidence so far, I'd have a Massive Attack Meltdown every summer if I could. The group have picked such a fascinating and balanced selection of live acts for this year's festival that they've risked making themselves seem like the least audacious proposition in their own line-up, particularly given their paucity of output over the last ten years (er, just the one new record and still waiting for the much-delayed 'Weather Underground').

Fleet Foxes seem completely overwhelmed that they've been invited to play a venue of the size and significance of the Festival Hall and no doubt its rather staid and serious atmosphere baffles them too. There's a lot of joking around between songs, and a general bewilderment at just how quickly Britain has embraced them. It's easy to see why this has happened - Robin Peckold has a voice that is at once sharp and warm, closely resembling Jim James from My Morning Jacket, although they lack that band's classic rawk predilections, instead crafting something more rustic and traditional. Their harmonies are precisely and intricately arranged, but the resulting collective timbre is also deeply compelling. The songs, particularly 'Oliver James' and 'Your Protector' seem more like stories than poems. Sometimes the lyrics are frustratingly forced - like the group are trying to capture some kind of folk ideal, preoccupied by nature and ritual. But the music has a soulful edge too, and the playing is consistently inspired, primal and beautiful.

Elbow therefore have a task on their hands, but they step up to the plate with admirable wit and charm. The first part of their set is dominated by material from new album 'The Seldom Seen Kid' and its predecessor 'Leaders of the Free World' and the songs sound both more precise and more beefy in their live incarnations. The group display their musicality eagerly, but also unpretentiously and Garvey's voice, both towering and believable, continues to mature. Many of these songs have real emotional power, and the title track from 'Leaders of the Free World' is much more potent and righteous in concert than on record.

About an hour into the show, they surprise us all by bringing on a substantial male voice choir, who creep on to the stage singing the chorus from 'Any Day Now'. It's a wonderful touch that immediately imbues this show with a special, one-off significance, as well as a real sense of fun. Garvey apologises for not being able to introduce the choir members individually, instead promising to refer to them collectively as 'Jeff', a commitment he dutifully upholds throughout the show. The whole project coalesces brilliantly on a simmering version of 'Starlings', the opening track from the new album, with the alarming horn bursts played not just from the stage, but from a number of the audience boxes. It's followed by an outrageously stirring 'New Born', with a protracted coda where the group make a feature of the venue's giant pipe organ. It could comfortably have gone on even longer.

The home straight of the show favours the band's terrace anthem singalong moments a bit too much for my taste, although 'Grace Under Pressure' sustains my interest chiefly through its rhythmic intricacy. 'One Day Like This', however, which closes an otherwise excellent performance, crosses the line into inspid cliche for me ('it's gonna be a beautiful day' etc - we can leave that to U2, can't we?).

I went to Thursday night's performance from Grace Jones with very modest expectations. So volatile and prone to diva-ish behaviour is this statuesque superstar that I'd half expected something of a Sly Stone experience. Would she mime or sing only to backing tracks? Would she be characteristically late on stage, and deliver a performance of larcenous brevity? What she in fact treated us to couldn't have been further from my fears. Her performance was at times bizarre, wickedly funny, outrageous, kitschy and flamboyant - all to be expected. But it was also a brilliantly executed statement rejuvenating her, at the grand age of 60 (but looking barely half that age), as one of pop music's most iconic figures.

She is introduced by a promo clip for a new song 'Corporate Cannibal' that offers a timely reminder of her terrifying magnetism. 'I consume my consumers', she intones creepily, 'without any sense of humour...I'm a man-eating machine'. Underneath her, the music seems to have taken something of an industrial turn, but the song's churning monotony offers an apposite sense of dread. Then, finally, a screen rises, her precision perfect band launch into the menacing dub of 'Nightclubbing' and she is revealed holding on to the rails of a platform for dear life. At the song's conclusion, she slithers provocatively down the stairs, and it starts to become clear that Grace Jones means to reclaim her lost status tonight.

Always realising the significance of image for a pop singer, she makes an exit from the stage after each and every song to make some alteration to her costume. There's all manner of elaborate headgear, masks and a worryingly thin g-string. Jones' most shrewd and perceptive attribute was to make her striking and androgynous image part of a more complete package - where music, appearance and vocal character artistically intertwine. Each new costume seems to bring with it a slightly different personality (she threatens to 'come out naked' at one stage). Her performance is highly physical and confrontational but also strangely self-deprecating and genuinely appreciating of the audience (at the end, she screams 'F*ck You! I love you all!' repeatedly - her peculiar method of showing her affection).

She keeps her promise to perform new material tonight - from an upcoming album to be released in September on the Wall of Sound label. She forgets the words, and ends up improvising - but the material sounds aggressive and life-affirming in equal measure, and stands up remarkably well when pitted against a raft of classic material. In this two-hour plus show, she hardly misses anything out - we get an hilarious patois introduction to 'My Jamaican Guy', a sensual 'Private Life', a theatrical 'La Vie En Rose', a relentless 'Demolition Man' and a thrilling 'Love Is The Drug'.

During a near perfect recreation of the intoxicating funk of 'Pull Up To The Bumper', she invites a stage invation. Fifty in the audience are reckless enough to accept her request - one tries to touch her and is quickly put back in their place: 'Nobody touches me, but me!' she commands and, quite frankly, no-one would ever dare to argue. She returns to clash a set of giant cymbals through a potent, slithering 'Warm Leatherette' and concludes the show with perhaps her most well known song 'Slave To The Rhythm'.

Her band are simply fantastic - with total mastery of reggae and funk groove playing. What is perhaps even more impressive is the sheer force and imagination of her voice. Those who thought that she couldn't sing when recording in the disco years should now regret their assessment of her abilities. Her camp, unbridled belting of 'La Vie En Rose' was hugely effective.

With no shame whatsoever and with considerable style, Jones has brought her wilderness years to a defiant and spectacular close. The new material bodes well for the completion of a quite tremendous comeback.

On Friday, the double bill of Terry Callier and Aloe Blacc at the Queen Elizabeth Hall asserted the relaxed mastery of the headline act and exposed the limitations of his support. Aloe Blacc was ably supported by a dexterous and innovative drummer - but he appeared to be in the wrong band. Blacc's lyrics, whilst no doubt sincere, proved stiflingly earnest and reliant on cliche. It's all very well understanding the great history of black popular music but it's incumbent on a new artist to add their own contribution to it. Blacc's set seemed to me to be nothing more than a smash and grab raid on his noble influences.

Callier, meanwhile, was in another league. Callier is a singer of imperious and magesterial quality, but with a charming and friendly demeanour that made his entire performance seem effortless. Even now, his straddling of the intersections between folk, soul and jazz still sounds invigorating and original. There are a lot of passions in this music, both personal and political, and a refreshing openness characterises his writing. The timbre of his voice is naturally mellifluous, but he can sometimes cut through with real attack and vigour. His superb band are virtuoso musicians - legendary guitarist Jim Mullen, the expressive percussionist Bosco d'Oliviera and the quietly inventive drummer Nick France all among them. Callier wisely allows them plenty of space, but the group reward him by placing their expressive talents firmly in the service of his remarkable songs. His performance had far more force, power and authority than any of those mock-virtuosos from the Brit School or X-Factor crowds could muster.

The full line-up of this year's Meltdown Festival is an embarrassment of riches that shames most of the major summer festival line-ups for their lack of courage and conviction. Some wonderful acts I sadly have already missed or won't be able to catch - Flying Lotus, Dalek, Tom Tom Club, Leila and George Clinton.