Teenage Fanclub, Koko, London

In a gig of few surprises, Scotland's most laid-back band reveal they have gone political; well, a little bit. "We've had a new prime minister since we played here last," the garrulous Norman Blake points out. "We met him once, he said he liked Big Star – he must have been briefed."

For those without an interest in spangly US power pop, Big Star are perhaps the most important influence on the Teenage Fanclub sound, just ahead of Byrdsian jangle and Beach Boys harmonies. In-jokes aside, few bands have come close to matching the Glasgow outfit's sunny charm, especially since the heyday of their 1991 album Bandwagonesque.

This London date, the first since 2006, is a warm-up for The Fannies' contribution to their home city's Celtic Connections festival that pits homegrown talent against global sounds and, judging by Blake's early nerves and Raymond McGinley's initial vocal efforts, they need it.

But after a few warm-up numbers the band hit their stride with "Star Sign" as Blake's fuzz meets lead guitarist McGinley's discordant shards. Each of the three writer/vocalists gets a fair share of the limelight. Blake handles the most robust tunes and between-song "humour".

Bassist Gerard Love seems to have aged not one day since The Fannies were influencing Nirvana. His boyish delivery adds a vulnerable touch to "Don't Look Back". The best moments come when his and Blake's voices meld into one honeyed strain, before McGinley finally finds his own range for the tender "Your Love Is the Place Where I Come From".

This is, ultimately, an exercise in nostalgia for the fortysomething crowd, self-deprecatingly referred to as the dadpit, who look only slightly younger than the band on stage. Blake gently reminds us they made an album, the self-released Man-Made, as recently as 2005. The delicate "Only With You", led by sparse keyboards, and the stern, Krautrock-flavoured drumbeat of "It's All In My Mind" add new twists to the Fannies' oeuvre without sounding totally compelling.

You can tick off all the songs that no gig of theirs would be complete without, from acoustic ballads to glam rock outs. They return for a second encore of "What You Do To Me", still surprising in its daring simplicity. Blake is effusive in gratitude, but his bandmates look eager to leave, as if aware they have become a credible alternative to The Proclaimers. With songs like these, though, they have nothing to be embarrassed about.