Grizzly Bear, the quartet from Brooklyn, New York, have quietly assumed a position of unassailable authority among the cognoscenti since the release of their third album Veckatimest this year. Combining post-rock, alt-rock and art-rock ingredients in one enigmatic package, it is a work of vague but sweeping complexity and insular grandeur, and was greeted with ecstatic reviews and an immediate placing in the Top Ten album chart in America. Radiohead’s guitarist Jonny Greenwood has declared them to be “his favourite band in the world”.

So expectations were understandably high on the first night of Grizzly Bear’s first British tour for two years — and the only date on which they were accompanied by the London Symphony Orchestra. The stage was decked out with a cluster of strange, free-standing trusses, from which dangled light bulbs in jars, like fruit hanging from the branches of trees. Smoke billowed out from a pair of cannon set at either side as the orchestra, conducted by Jim Holmes, took their seats in the centre area of the stage followed by the band, who lined up across the front.

What followed was an ornate yet curiously disengaged presentation in which symphonic passages of delicacy and precision were interwoven with band arrangements and harmony vocals that drifted hither and yon in pleasing symmetry but often without any clear purpose or direction. Ed Droste, the founder of the group sang in a high, tremulous voice that was swathed in such dense layers of echo that it was impossible to hear the words, let alone to detect any potential meaning in them. Daniel Rossen, who played guitar and sang lead on some of the numbers, fared somewhat better and his vocal on While you Wait for the Others was a high point of the show.

The set was dominated by songs from Veckatimest. The bobbing keyboard intro to Two Weeks brought a cheer of recognition and the mood of cerebral solemnity thawed as the drummer Christopher Bear hammered away at an old, badly-warped cymbal towards the end of the number. Dory was a more typically mysterious piece, which sailed along on a sea of mournful abstractions but never seemed to get to the point.

The orchestral arrangements added a rich, symphonic dimension to the music and there were passages of tremendous scope and ambition. But there is a thin line between achingly beautiful and achingly dull, and for all the swirling majesty of the performance there were times when these four earnest men with their furrowed brows came perilously close to crossing it.

Droste referred several times to the enormous sense of privilege that he and the band felt at being part of such an event. A shame it wasn’t just a bit more fun.

Touring: Glasgow ABC, tonight; Manchester Cathedral, Weds; Leeds Metropolitan University, Thurs; Bristol Anson Rooms, Fri

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