Kate & Anna McGarrigle, Bridgewater Hall, Manchester

No one coughed, rustled or spoke - indeed, people seemed scarcely to breathe. It was as if their fans were afraid that the elfin pair might vanish in a trice. They did vanish, of course, but not before they had featured a remarkable range of songs, many from their latest album, a nod to their French-Canadian roots, La vache qui pleure. The title ("The Crying Cow") may be a pun on La vache qui rit, a brand of processed cheese, but there's nothing cheesy about the music, in which Kate plays guitars, banjo, piano and violin, Anna adds guitar, accordion and the occasional dash of synthesiser, and a quartet of blokes help out on the harmonies.

The events that have coloured their singer-songwriting careers - the spawning of Rufus and Martha Wainwright, and Lily Lanken, in particular, and the coming and going of love - have all informed their music-making. As their set progressed, it became clear that some of their more recent numbers have become more gutsy but no less refreshing in style, even if their improvised presentation was laid-back to the extent of seeming chaotic.

The a cappella rendering of the Bahamian spiritual "Dig My Grave" was thrilling; the wistful "Sunflower", with its delicate melodic counterpoint on violin, captivating. Another favourite, "Goin' back to Harlan", showed that the McGarrigle sisters' highly original take on jazz, blues, old pop and French and English ballads, has lost none of its intangible magic. Anna's edgy soprano and Kate's mellow mezzo wove in and out of deceptively intricate arrangements.