Big Star, Shepherds Bush Empire, London

Alex Chilton was a teenybopper pin-up via his first band The Box Tops. In 1971 Chilton teamed up with Chris Bell, an old mate from his home town of Memphis, Tennessee, to join a band called Icewater. He changed the name to Big Star, and they made a debut album, No 1 Record, that critics acclaimed as a masterpiece, but which was heard by virtually no one on account of abysmal distribution.

They split, then reconvened to release Radio City in 1974. Bell left again, for good this time – he was killed in a car accident in 1978, the year Big Star's last album Third/Sister Lover was released.

Destined to be big in the future, Big Star became a retro cult, their melodic, existential pop proving highly durable. By the Nineties everyone from REM to Primal Scream hailed them as a major influence. A virtually ad-hoc reconvening of Big Star saw Chilton and original drummer Jody Stephens joined by Jon Auer and Ken Stringfellow from US pop band The Posies. A fourth Big Star studio album, In Space, hit the racks in 2005.

Now this one-off gig, before a headlining slot at the Rhythm Festival in Bedfordshire, seems mandatory for the legions of fortysomething fanboys. Following a loopily lyrical solo set from Robyn Hitchcock, Big Star take the stage, the two younger musicians most prominent on second guitar and bass, and Chilton to one side, bending under the weight of his Gibson.

He may resemble a cross between Tom Paulin and Norman Bates in a geography teacher's jacket, but Chilton has a catalogue of great, intensely emotional pop. But somehow much of the magic sounds diminished, lost in guitars that dominate too coarsely, and backing vocals that are louder than Chilton's lead.

He gives us great songs – "Battle of El Goodo", "In the Street", "Way Out West", "Thank You Friends" – but they are weighed down by dull guitar work. These songs need to be stripped naked, but here they're clothed in electric wool. Chamber pieces get turned into stadium garage rock. It's only on a handful of songs, including a delightful "For You", and "September Gurls", that the spaces open up for Chilton to put his stamp on proceedings.