"British Sea Power are a band that journalists love; if only for the reason that they give us so much more to write about than music." So suggested fellow Quietus writer Ben Graham on the release of the band's new LP Machineries Of Joy. But what more is there to write about the band? Eccentric, quixotic, whimsical, utopian, British Sea Power provide a myriad of opportunities for journalistic excess. It's true that a group that came to our attention through their arcane obsessions and love of wildlife certainly invite such superlatives. But in many ways it's their mixing of the alternative with the conventional that makes them so interesting. This can be felt in the way they explore the peripheries of rock, managing to sound like a lot of different bands at various times, while sounding like no one else. This has much to do with the ethereal undertones that run through their music, so even when they are delivering a hands-in-the-air anthems like 'Waving Flags', they do so with an air of mystique and meaning.

The band crafted their art through their Club Sea Power nights in Brighton, which included guest spots with the Suffolk folk group the Copper Family. And the folk element of BSP's own music and aesthetic is perhaps something that has been under-appreciated by a press caught up in their indie fixations. But to these ears this is where the band starts to veer away from those contemporaries they are most regularly compared to (be that Elbow or Arcade Fire). In both their imagery and sound, they certainly draw on what Rob Young, in his essential book Electric Eden, termed "the battle between the progressive push and the nostalgic pull". Their folk leanings can be sensed strongly through their obsessions with people and nature, whether composing an anthem to humanity like 'Machineries of Joy' or writing the soundtracks to Man Of Aran and From The Sea To The Land Beyond. Perhaps that is why live performance, bringing their music to as many as possible and fostering a real sense of community among their fans, has also been so important to them. Playing on top of the Great Wall of China, on an islet in the Arctic, or down a Cornish slate mine, BSP's gigs have become the stuff of legend. And although the Shepherd's Bush Empire is a more conventional setting for the band, the charcoal drawings of wildlife, Ordnance Survey maps, shopping bags, and old-fashioned hair pomade on sale as we enter the venue hint at the delights to come. There's also nothing conventional about the format of the show. Cutting it fine, we discover the earlier start time of 7.30pm was so the band can play two sets split by the not inconsiderable talents of Toy. It proves an inspired choice with two differently textured sets from the headliners, and the chance to see a much tipped support band in front of a full house.

BSP's habit of dressing the venue with trees and other wood life goes back to those early sessions in Brighton, and it adds to the sense of occasion as the band take to the stage for their first set. No-one works melody quite like BSP, and the interweaving guitars and vocals of 'Hail Holy Queen' are given an added poignancy by the gently soaring violin of Abi Fry and Phil Sumner's mournful cornet. The folk blues of 'Come Wander With Me' from the Man From Aran sends a hush around the hall with Fry's harmonies adding to the resonance of a song deep in feeling. A purple hue bathes the stage for 'Blackout', complimenting the wooziness of the lyrics. The acoustic beauty of 'Salty Water' from the Remember Me EP and 'What You Need Most' from the new album rounds off a warm and enticing section of music, displaying the reflective beauty of this most versatile band.

With echoes of bands such as The Horrors and Wooden Shjips, Heavenly signings Toy are in fact carving out their own space in psychedelic pop. This has much to do with the motorik drumming and a good ear for a pop hook. With their heads down and minds high they provide a soulful maelstrom that builds and builds, ending half an hour later in a haze of feedback and applause.  

The trees and twigs wrapped around microphone stands and peeping up beside the drum kit flash with fairy lights as BSP make their way back onto the stage for their second set. The band's spirit in diversity can be traced back to those early Club Sea Power nights, where you could find the acoustic folk of the Copper Family followed by the rockabilly of The Eighties Matchbox B-Line Disaster interspersed by a 1930s DJ set. And after the gentle caress of the first set it's time for the band to get dirty with the storming power pop of 'Remember Me' and the post punk assault of 'Apologies To Insect Life', eliciting a healthy dose of pogoing from their fervent following. Even dirtier, dark in fact, is the cautious tail of excess that is 'K-Hole' from their new LP. Three songs in we need some relief. It comes in the form of 'Bear', that lovely slice of melodic pop from their Zeus EP. No band mixes the bombastic with the sublime quite like BSP and there are some jaw-dropping moments tonight where any rock excesses are countered by their dreamlike atmosphere. That atmosphere turns murkier on 'No Lucifer' where cut-ups of the video (somewhere between Luis Bunuel and Kenneth Anger) adds to the darkness. The haunting 'When A Warm Wind Blows Through The Grass' from their new LP is welcomed like an old classic, as is 'Machineries of Joy' which is the kind of anthem only BSP could make without sounding pompous.

As if to force that point home they follow with 'Waving Flags', the anti-nationalist anthem that proves the best antidote to the day's Evening Standard Thatcher special. Equally epic in scale is 'Great Skua', still one of the most moving pieces of music the group have made, and sounding majestic ringing trough this old hall tonight. Lovers of Open Season, perhaps their least valued but in my opinion best LP, are kept happy by a rousing performance of 'Please Stand Up' while new album tracks like 'A Light Above Ascending' have even more immediacy live. A joyously shambolic encore of 'Loving Animals', featuring a play fight from the two giant bears that have been leading the dancing on and off all night, rounds off a typically multi-faceted night of music from one of our most enigmatic yet engaging bands.