Music review: Cat Power provides smoky vocals at the Roundhouse, London

Cat Power smoulders at the Roundhouse (Rex Features)

Stop mumbling, former RSC star Imogen Stubbs has advised aspiring actors, though the same counsel could apply to the singer heading to the rear of the stage to light a not-so-crafty cigarette. For while capable of reaching earthily soulful heights, the voice of Chan Marshall, aka Cat Power, disappears between numbers.

Finding such a complaint worthy of note indicates the artist's improved well-being. Beset by substance abuse and mental issues, she has long been known as an erratic performer, cutting short sets or rambling. Yet last year's album Sun was her most poppy, upbeat work to date, helping it scale the heights of the US Top 10. Unfortunately, Power had to postpone her 2012 European dates due to a stress-related illness, though now exudes tanned health under a shock of bleached blonde hair. 

Confidently taking charge of the wide expanse unoccupied by her diffident band – the bassist doubles up on percussion at the back and a guitarist lurks at one side – Power appears ready to display Sun's new-found positivity. Yet a distracted, fidgety air distracts attention and her voice lacks the power comparisons with Nina Simone suggested - somewhere between PJ Harvey and recent Sinead O'Connor being more accurate. Drums and percussion in unison easily outmatch her husky vocal on "Manhattan", though she and the band give a sinuous Bad Seeds feel to "Metal Heart".

Seemingly dragged from a Williamsburg gutter, Power's backing group struggle with old and recent tunes. They are sketchy on "Human Being", one of Sun's more austere electropop moments, and play "Always On My Own" like an insipid Joy Division. Recreating the warm Memphis soul of The Greatest's title track, its 2006 predecessor in terms of original material, the four-piece sound rough and ungainly. Power, too, fails to convince with her takes on contemporary R'n'B, lacking the necessary snap on "3,6,9" and "Peace And Love".

Tackling more classic styles, and once the sound desk has her measure, she provides some memorable moments. Best is the simple beauty of the track missed from the original release of Sun, "Bully", an aching ode to a lost friend “standing on the street in a hospital sheet”. Almost as compelling is the glowing optimism of Power's life-affirming anthem "Nothing But Time". At the end she is tossing flowers into the audience, then ripping up set lists as extra souvenirs - an eccentric show of gratitude after such an uneven night.