Dirty Three / Cat Power, Shepherd's Bush Empire, London

In retrospect, any concert featuring the violin-driven devilry of Australia's the Dirty Three and the otherworldly Southern blues of Cat Power was bound to be choppier than most. Indeed, there was an eye-of-the-storm quality about both acts at Shepherd's Bush, albeit of a different type. Chan "Cat Power" Marshall doesn't start her solo slot until 10 minutes after she ambles on stage. "I'm high on crack and I don't even know it!" she giggles, mystifyingly, before starting a song, stopping it, moving to the guitar, going back to the piano, getting a man from the crowd to be her cigarette-holder.... It's fair to say, she's off on one.

Marshall has never been noted for slick professionalism, and while it would be a stretch to say that everything makes sense when she begins to sing, she does wring enough emotion from "I Don't Blame You" to justify the reverence she's held in. She's infuriating, but after 45 minutes speckled with hints of wayward, of-the-moment brilliance, you want to see her again soon, in the hope that she'll nail it next time.

There's a rumour that this tour might be the Dirty Three's final bow which goes some way towards explaining the intensity of their show. Then again, with violinist Warren Ellis for a frontman, you're guaranteed a spectacle. The sometime Bad Seed is one of the few men who can challenge Nick Cave for demonic charisma on stage, and he's on ragged and ravaged form tonight, dredging up ungodly howls from his instrument as he jigs about in a lean whirl of elbows, hair and kicking heels.

He's got the deranged preacher-cum-virtuoso role down to a T, and the crackpot vignettes with which he introduces each song are bonkers enough to see him certified.

Musically, seasick sketches and soundscapes are the Dirty Three's shtick, Ellis's virile violin riding the ululating backing of Jim White's part-bashed, part-brushed drums and Mick Turner's minimal guitar. It's a simple template, sure, and their latest album, She Has No Strings Apollo, marks no change of direction. But they take their songs everywhere anyway, veering giddily from small-hours melancholy to waves of noise with a seemingly telepathic, improvisational flair that's nakedly powerful live.

"It's the sound of one million fucking hearts exploding," grins Ellis, introducing "1000 Miles", from 1996's Horse Stories. Given the clamour for an extra encore, he's not far wrong. If this was their penultimate London show, they'll be sorely missed. It's been emotional.