Eliza Carthy may have only just turned 26, but she has already crammed an exceptional career into a very few years. She has shaken up the British folk scene with her solo albums and collaborations with her parents, Martin Carthy and Norma Waterson, released an album of her own folk-rock pop songs, and still found time to work with anyone from Joan Baez to Bill Frisell. She has now become an exceptional live performer.

With the new album, Anglicana, she moves back to traditional songs, and her versions are as remarkable for the vitality and originality of the settings as for the new maturity in her singing. In the past she has shown that she can match her father's instrumental skills (though on fiddle, rather than guitar), but now she has also begun to match her mother's musical and emotional range and easy confidence in her vocals.

At the Purcell Room she came on stage sporting blonde hair (rather than the red and then blue of recent years) and played two lengthy sets in which she switched styles or instrumentation for almost every song. First there were solo pieces, on which she backed herself on guitar and then fiddle, moving from traditional songs to her own drifting pop ballad, Whispers of Summer. Then came a series of duets, with her witty accordionist Martin Green and multi-instrumentalist Ben Ivitsky, ranging from dance tunes to a stomping country blues. For the best duet of the evening she was joined by her father for a delicate and thoughtful guitar-and-fiddle instrumental, Dr MCMBE, which she wrote to celebrate her dad's 60th birthday.

The second half was even more lively, with up to eight musicians joining her on stage. There were no beards or flares here, but a set of cool young musicians with cropped hair and sports shirts. They switched from a sparse and aggressive percussion-and-fiddle-powered treatment of the murder ballad Worcester City to a gutsy work-out on Ten Thousand Miles (with added vocals from Heather Macleod) and an adventurous bluesy reworking of the traditional Willow Tree.

Then the band departed so their leader could provide another reminder of what a great singer she has become, with an unaccompanied solo treatment of Bold Privateer. Magnificent.