When listening to any new U2 record you're immediately confronted by the fact that you're listening to a very different band to the one that was at the height of its power in the 80s and 90s. Long gone are the chunky, post-punk riffs from 'Boy' and 'War', as are the hyper-political elements which defined so much of their music in that nine year period between 'The Unforgettable Fire' and 'Zooropa' when U2 were at their best.

In their stead we've become accustomed to U2 being a band who principally trade on the glories of yesteryear. When bands have been in this game for a long time the inevitable erosion of their critical voice stops becoming a nagging afterthought and eventually starts to define them. It happened to Bob Dylan, it happened to the Rolling Stones and it would be naive to suggest that U2 were impervious to a similar creative decline.

Indeed the best parts of 'Songs of Innocence', the album which U2 unexpectedly gave away for free on iTunes yesterday, hark back to memories from the band's heyday.

'Every Breaking Wave' contains classic Bono vocals while 'Iris (Hold Me Close)', a song about Bono's mother who died when he was a teenager, displays a lyrical deftness alongside trademark artistry from The Edge and Adam Clayton. The excellent 'Cedarwood Road' and 'Sleep Like A Baby Tonight' are the two best cuts from the record but you'd be hard pressed to find a space for them on an album like 'Achtung Baby'.

'The Troubles', as you might expect, is one of the more political tracks on 'Songs of Innocence'. In it Bono sings: "I have a will for survival, so you can hurt me and then hurt me some more. I can live with denial but you're not my troubles anymore." When held up to the light the song reveals Bono at his most reflective but tacitly lacking any of the raw energy through which 'Sunday Bloody Sunday' sends shivers up your spine.

So much of U2's best work has come in tandem with producer Brian Eno. This time around Eno's role has been recast to producer-de-jour Danger Mouse, responsible for so much of the Black Keys' recent critical and commercial success and, while his influence on the album is largely restrained, he infuses the album with a distinct polished sheen.

That's one of the truer criticisms of 'Songs of Innocence'. Whereas on previous releases, you could feel the energy of the room in which U2 were recording. You got the sense that something important was happening, that Bono was the chief artist painting an ever-expanding sonic canvas. This time around it all feels a bit too tight, a bit too restrained and constricting.

Now in their fourth decade of releasing music, U2 have found themselves at a creative impasse. It's estimated that 'Songs of Innocence' has already earned U2 around $100 million from Apple and when you add ancillary sales and touring profits, the band look set to have one of their most profitable albums yet.

Even though U2 are in their least creatively fruitful period of their careers they still manage to stay one step ahead of the game. And, in a sense, that's Bono's true artistry.

Review by John Balfe | TWO POINT FIVE STARS

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