Jeff Tweedy’s first band, Uncle Tupelo, played American roots music with the vigour of punk rock, and inadvertently started the thriving scene known as alt-country. With his second band, Wilco, he has become the genre’s biggest star and its biggest critic.

Consequently, the past two Wilco albums have found Tweedy apparently striving to frighten off his more hidebound followers – Yankee Hotel Foxtrot (2002) planted his anguished songs in a hailstorm of electronic static, while A Ghost is Born (2004) included a solid 15 minutes of drone. Seemingly designed to alienate, these two fantastic albums enjoyed a success that actually proved Wilco’s fans were a lot more open-minded than anyone had assumed. Wilco were now the biggest band of their kind since REM. Whatever would he do next?

The answer, naturally, is confound expectations. Sky Blue Sky sounds like a return to alt-country. The songs are generally mellow, often recalling the woody and soulful folk of the Band. After being addicted at various times to alcohol and painkillers, and enduring numerous scraps with old record labels and long-departed bandmates, Tweedy’s new contentment shines through on What Light and On and On and On.

A couple of things are striking. First, Tweedy is better at this stuff than any of his contemporaries – Ryan Adams would kill to write something as fluently crafted as You Are My Face. Second, the current lineup of Wilco is packed with virtuoso experimentalists who add discreet twists to these songs. Impossible Germany, in particular, has vivid passages that are a match for the Grateful Dead.

The result is an album that reveals hidden depths every time it is played. One suspects, though, that Wilco’s future might not be so easy-going. Who would bet against Tweedy following this warm and approachable set with an hour of cacophonous skronk? Some of us live in hope, anyway.

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