unabashed idealism rooted in spiritual aspiration. At their best, these Irishmen have proven – just as Springsteen and the Who did – that the same penchant for epic musical and verbal gestures that leads many artists to self-parody can, in more inspired hands, fuel the unforgettable fire that defines great rock & roll.

At their worst ... well, the half-live double album Rattle and Hum (1988) – the product of U2's self-conscious infatuation with American roots music – wasn't a full-out disaster, but it was misguided and bombastic enough to warrant concern. With Achtung Baby, U2 is once again trying to broaden its musical palette, but this time its ambitions are realized. Working with producers who have lent discipline and nuance to the group's previous albums – Daniel Lanois oversees the entire album, with Brian Eno and Steve Lillywhite assisting on a number of songs – U2 sets out to experiment rather than pay homage. In doing so, the band is able to draw confidently and consistently on its own native strengths.

Most conspicuous among the new elements that U2 incorporates on Achtung are hip-hop-derived electronic beats. The band uses these dance-music staples on about half of the album's twelve tracks, often layering them into guitar heavy mixes the way that many young English bands like Happy Mondays and Jesus Jones have done in recent years. "Mysterious Ways" is a standout among these songs, sporting an ebullient hook and a guitar solo in which the Edge segues from one of his signature bursts of light into an insidious funk riff.

Elsewhere, as in the fit of distortion and feedback that opens "Who's Gonna Ride Your Wild Horses," Edge evokes the cacophony and electronic daring of noise bands like Sonic Youth. Indeed Edge's boldness on Achtung is key to the album's adventurous spirit. His plangent, minimalist guitar style – among the most distinctive and imitated in modern rock – has always made inspired use of devices like echo and reverb; his shimmering washes of color on "Until the End of the World" and soaring peals on "Even Better Than the Real Thing" and "Ultraviolet (Light My Way)" are instantly recognizable. But other tracks find the guitarist crafting harder textures and flashing a new arsenal of effects. On the first cut, "Zoo Station," he uses his guitar as a rhythm instrument, repeating a dark, buzzin