The Fiery Furnaces, King's College, London

Matt and Eleanor Friedberger have been called many things, from kooky folkies to pop eggheads, but "rock monsters" must be a new tag for them. That, though, was the impression of a night dominated by Matt's guitar pyro-technics as Eleanor glowered from beneath her fringe. If the siblings intended to put clear water between themselves and Franz Ferdinand, the band of Eleanor's boyfriend Alex Kapranos, they succeeded.

Not that this was really necessary. Last October's narrative album Rehearsing the Choir, in which their grandmother tells her story, was half-baked. While recording that, they also laid down tracks for the more straightforward Bitter Tea, released this week.

Their fourth album still contains enough backwards voices and daft keyboard interventions to alarm casual listeners, though that was dispensed with live. Instead, the pair brandished guitars on either side of the stage with the rhythm section at the back.

While Eleanor did her strident, though introverted, Patti Smith impression, Matt went through a wide array of styles. In the past, The Fiery Furnaces have chopped and changed between songs in long medleys. Tonight, they showed more respect for the expectations of the audience, but their sturdy rock line-up delivered a sound so different from the recorded versions of their songs that fans hesitated to welcome them. Only "My Dog Was Lost But Now He's Found" won a relieved cheer.

Such material, with its frazzled psych-rock base, tips its hat to Captain Beefheart. As the songs became more complex, Matt - aside from his puny vocal contribution - threw in Tom Verlaine twitchy solos, ominous descending chords recalling the Dead Kennedys and even trendy punk funk, though not the polished kind favoured by Eleanor's beau; it was dense, grinding, much like early Gang of Four.

The Bitter Tea numbers revealed how the duo continue to build from disparate units, rather than resort to conventional verse/chorus structures. Their favoured subject matter remains travel and yearning: the melancholic, yet soaring "Benton Harbor Blues" could be Television covering U2, though the likes of "Teach Me Sweetheart" lack the necessary hooks to carry its parts.

Though the New York duo display a vast range of tastes, on this night the whole was flat and undefined. Matt didn't vary the intensity of his playing within songs; Eleanor sang only in a stern voice, an unnecessarily restrictive tactic.