Donegal's Clannad have been one of Ireland's most successful musical exports: in a career spanning 30 years, they have conquered foreign charts and received numerous awards, including a Grammy for 1998's Landmarks. Their brand of ethereal folk rock has not only made a lasting impact on Hollywood soundtracks (for films from Patriot Games to Last of the Mohicans), but also spawned the irksome career of singer Moya Brennan's sister Enya. This is a legacy that the world could have done without. Whatever Clannad's intentions, the swathes of 90s easy listening pseudo-folk and countless corporate relaxation tapes they inspired make it difficult to appreciate the freshness this music might have had 25 years ago.

Appearing here on their first tour in 10 years, they seem remarkably relaxed, with the band fluffing their intros on several occasions and Ciarán Brennan constantly interrupting sister Moya when she addresses the audience. More important than this latent sibling rivalry is the way in which the music has dated: their fondness for trashy synths and drive-rock guitar solos just grates now.

The vocal harmonies of Mhorag 'S Na Horo Gheallaidh are pretty but, at its worst, the plodding pace and lack of substance serve up the sort of music American Psycho Patrick Bateman would plonk on after a particularly vigorous gym session. Even in a set containing several film scores, other songs, such as Trail of Tears, feel manipulative in their declarations of their own authenticity. Combined with Moya Brennan's battle re-enactment silver robe and talk of mythology, much of the experience is like watching a particularly naff tourist board advert.

· At Alexandra Theatre, Birmingham, tomorrow. Box office: 0870 607 7533. Then touring.