“Big bass, big drums, siren, mad.” Those simple ingredients that Tom Rowlands and Ed Simons identified as the essence of their early sound have served the Chemical Brothers well.

Their debut release under The Dust Brothers moniker, ‘Song for the Siren’, defined a dancefloor demolition template that still ranks as one of the finest and most influential exercises in electronic music.

That remarkable 12” was fashioned in the pair’s bedrooms, while tellingly, Come With Us, the Chemicals fourth and most disappointing album, was painstakingly put together over 18 months in a swish state of the art London studio.

It begins promisingly, but then again Tom and Ed have always been best at knocking out killer opening tracks. A booming voice announces; “Come with us/And leave your hurt behind/Bright and clear we see the light/All the universe is at your side/Please lead us to other suns more bright/Behold!/They’re coming back...” Mammoth drum rolls kick in and those psychedelic loops of fury swirl. Make no mistake, this could only be a Chemicals album.

Last year’s low key single ‘It Began in Afrika’ follows, ploughing a tough tribal furrow of commercial ethno-techno, shuddering vocals and ‘Higher State of Consciousness’ style bleeps. Then, quite frankly, this rave up gets very dull indeed.

‘Galaxy Bounce’ is a rehash of those rumbling basslines they turned into a spectacular UK number one with ‘Block Rockin’ Beats’. First single proper ‘Star Guitar’ is a lame attempt at re-packaging Balearic melodies into psychedelic by numbers shapes. Its ethereal mantra; “You gotta feel what I feel / You gotta take what I take” leaves no doubt that Come With Us is intended to be served with the appropriate chemical prescription, but it’s the sort of anthem we’ve all heard ad nauseam by now.

The album finds some form in the Aphex Twin-sounding chimes and drones of ‘My Elastic Eye’, which could suggest that there is something in the water in South London’s Elephant and Castle district seeing as Richard D. James’s patch is just an Evening Standard seller’s shout away. Regular chemical chanteuse Beth Orton contributes to the fine electro-ballad ‘This State We’re In’, but it’s still not on a par with Orton’s previous efforts with the Brothers on ‘Alive Alone’ from the groudbreaking Exit Planet Dust or ‘Where Do I Begin?’ from their most exciting long player, Dig Your Own Hole.

To leave us on a suitably low note, Richard Ashcroft pops up for a flatulent finale entitled ‘The Test’, ranting away on his usual “music is mystic man” tip.

As the Chemicals’ weakest hour closes, one is left bewildered by just how much the mighty have fallen. It is not that they don’t work hard enough or have lost their knack at production, it’s just that no amount of studio gloss can disguise these paltry half-baked ideas.

If this was a debut album from some dayglo Gatecrasher kids then fine, but knowing what they’re capable of, the brothers really gotta work it out all over again.