Ice Cube, IndigO2, London<br/>Friendly Fires, Roundhouse, London

Cube's longevity in the fast-changing world of rap is a thing of wonder; and seeing an icon in the flesh is always a thrill

After all these years, Ice Cube retains the permanently crocheted, if not knitted, brow of a man who's concentrating hard on unscrambling a particularly riddlesome Rubik's Cube.

What he's probably trying to figure out is how one man could be so blessed as to be present at the epicentre of not one, not two, but three game-changing moments in hip hop history.

In a genre where you're only ever one flop record away from joining Ja Rule and Busta Rhymes on the shelves of Scope, the Cube's longevity is a thing of wonder. He's been present at so many births that when his stage sidekick, the lavatorially-named WC, tells him "They want you to start at the beginning", there's mock-confusion over which beginning he means.

He means Gangsta Rap, of which NWA weren't strictly the first (see Ice-T, see any number of obscure pioneers), but they took it overground and kicked down the doors of the mainstream. Musically, NWA sounded tinpot and outdated even in 1989, but in terms of aggression and unapologetic hardcore attitude, they were revolutionary. Their fuck-tha-police stance still resonates so strongly on both sides of the Atlantic that, before the show, a spokesman for leukaemia charity ACLT has to reassure us that the blood samples they're seeking won't be given to the Met's DNA database.

The second beginning was that most maligned of rap sub-genres, G-Funk. Yes, it was crystallised by his former bandmate Dr Dre, but it reached its pinnacle with Cube's "You Know How We Do It". Tonight it's just sublime, that squealing sine-wave synth backing the brags of the rhymes, as the notional neons of the Vegas strip reflect off the beeswaxed hood of his theoretical ride.

The third was Horrorcore, the short-lived but massively influential fad which peaked when Cube reunited with Dre for the Californian-Gothic classic "Natural Born Killaz", another highlight tonight, and a track which was only possible because Cube retained a dignified distance from the unseemly, if bloody hilarious, feud between Dr Dre and fellow NWA alumnus Eazy-E. Even now, "Killaz" leaves your jaw open with lines like "So I'm a pull a fuckin' Jeffrey Dahmer/Now I'm suicidal, just like Nirvana ...", written when the soil on Kurt's grave was fresh.

It couldn't last, of course, and Cube ran out of steam when he became embroiled in a film career which moved from the epochal Boyz * the Hood via half-decent claustrophobic gangland thriller Trespass and dumbass stoner comedy Friday to the nadir of snakesploitation flick Anaconda.

Since turning his attention back to music, making perfectly good, if unmemorable releases with his Westside Connection crew, he's inevitably lost touch with the zeitgeist. But seeing a hip hop icon in the flesh is still a thrill, and Cube – built for comfort not speed, a blue comb jammed into his microphone-like mini-afro, a diamante W on his shirt echoing the sparkles on his sneakers – has got charisma to burn, and skills to match. As the "Pyroclastic Flow" interlude puts it, with only minor exaggeration, he's like "Red hot lava mixed with saliva/Pulverising everything in its wake".

Just how much the rap game has changed since his heyday, however, is illustrated by overhead shots of Krazy Tunes' DJ console, containing just one Technics turntable but three Pioneer CDJ decks. And by the moment in his Isleys-sampling anthem "It Was a Good Day" where he's "halfway home and my pager's still blowing up". Mummy, what's a pager?

Some styles of music are more durable even than the cockroach, and one of them, against all forecasts, is the loose umbrella of indie-dance. From ACR through the Mondays to The Rapture and New Rave, the general idea of indie rock that you can dance to, or dance music with an indie rock sensibility, is a resilient one. It's a prime reason why Friendly Fires, a fine but unassuming band, are able to rub shoulders with the big boys at the iTunes Festival.

What must it be like being in a band plenty of people kind of like but nobody truly adores? Friendly Fires' last album went Top 10, but you'll never meet a Friendly Fires nutjob, or find an internet message board devoted to intense analysis of their art. They could pass you in the street unmolested, these regulation young men with their cheesecloth shirts and their standard stubble. Well, apart from the bald, middle-aged man with grey side-tufts who parps his sax with uncurbed enthusiasm. Undeniably it twinkles, their cowbell-bashing syncopated punk-funk with its cascading three-note arpeggios. They're essentially Foals without the troublesome aura of art and intellect, and that has its place. And "Paris" is a tune and a half, which has previously disinterested punters clattering back through the Roundhouse doors screaming "Ooh, I like this one!" But if Friendly Fires weren't here, would anyone honestly miss them?

Next Week:

Simon Price witnesses a father and son reunion from Rufus and Loudon Wainwright

Rock Choice

Bellowhead, Gruff Rhys and The Go! Team are among the highlights of Oxfordshire's compact Truck Festival at Hill Farm, Steventon (Fri to Sun). Secret Garden Party brings an eclectic line-up including Martha Reeves & the Vandellas, Leftfield, Blondie and CW Stoneking to a not-really-that-secret garden near Huntingdon, Cambs (Thu to Sun).