The need to push the boundaries has tested their friendship, their skills as musicians and their very sanity as they’ve evolved from a Britpop band into one of the most creative, provocative and perverse musical outfits.

In recent years the polarising work of Kid A, Amnesiac and Hail to the Thief suggested their stranglehold over the title of most commercially and critically successful band in the world was over.

However, there is no chiasmic divide in the importance music fans place on the chance to see Radiohead live — it remains one of most eagerly awaited events on any musical calendar.

Next Tuesday at the Meadowbank Stadium, Edinburgh, a sell-out crowd will witness what promises to be a reinvigorated Radiohead, still without a record deal but as important as ever.

The reason for such optimism lie with the words of singer Thom Yorke, who fresh from the successful release of his debut solo album The Eraser, a delicate, cautionary and sometimes beautiful record, who appears to be more at ease with himself, his band and their future.

“Having done something that’s not like Radiohead makes me realise how mad the group sort of dynamic is,” he conceded.

“It’s not something you just take for granted and can switch on and off. It actually takes work and everybody wanting to do it.

“One of the reasons to get back together to tour was to do something more direct. It doesn’t mean we’ll carry on being direct — that’s just what we’re doing at the moment.”

Without a record deal since the release of Hail to the Thief, this summer’s small burst of dates across Europe and North America has seen fans used as guinea pigs with new songs previewed including 15 Step, Down is the New Up and House of Cards.

However, any suggestion that the new material carries a calculated, more uplifting feel seems to grate with Yorke.

“I think it has always been the same. Loads of the music on OK Computer is extremely uplifting,” he explains.

“It’s only when you read the words that you would think otherwise. That’s just the kind of way it is.

“The whole point of creating music for me is to give voice to things that aren’t normally given voice to, and a lot of those things are extremely negative.”

But regardless of what tone any new material exhibits, there can be no doubting Radiohead’s spirit of political and musical independence will strike a note with those fortunate enough to attend next week’s concert.

Lots of bands have said they wanted to reinvent themselves with every release. The difference is Radiohead have done so.

Self-belief can be a dangerous thing. A little over a year ago, four guys from Leicester departed the music scene to begin work on their second album with words of praise from touring buddies the Gallagher brothers ringing in their ears.

Since then, new material has been kept under wraps as the excitement builds towards its official unveiling on August 28.

In the meantime Kasabian have returned to the live scene bragging that they’re the best band in the world, just you wait and see.

The capacity crowd at Edinburgh’s Corn Exchange prove one thing before the show has even begun — Kasabian transcend indie snobbery. Tonight’s crowd is not your typical NME scene with trilbies, white hosepipe jeans and the ironic badges so often witnessed at a gig these days.

Instead this is love and devotion for the masses, the young and old, male and female, the beautiful people and the down right ugly can all worship at the throne of Kasabian.

Most are already soaked in sweat by the time the familiar figures of Kasabian take to the stage and launch into new song Shoot the Runner. The soaring and instantly anthemic introduction is propelled along by handclaps and a stomping drum roll. It’s glam rock with a difference — it’s filthy and fantastic.

New songs such as the epic, string laden Sunrise and the chaotic jackhammer beats of Aponea merge into the raging classics as frontman Tom Meighan refuses to the let the pace drop.

Processed Beats, L.S.F., Butcher Blues and Reason is Treason all provoke riotous scenes of mob love as the heavyweight choruses deliver devastating blows to the senses one after the other.

It doesn’t matter who you’re standing next to, you cannot fail to be swept away by the chanting and sea of sweaty bodies, all bouncing to the beat. As the millionth pint of lager soars through the air not even the sight of a sweaty Ned depositing his supper on the floor can spoil the euphoria. Returning for the encore, new song “Stuntman” sees Tom share vocal duties with cohort Serge Pizzorno and the two verbally joust as the song reaches a crushing crescendo of white light.

But it’s the explosive Club Foot that brings proceedings to a worthy end. As the crowd unites one final time in homage to their heroes Tom incites a mass sing-a-long that is a joy to behold from within the throng.

As the lights go up Tom and Serge thank the crowd for being Scottish and bequeath the title of best crowd ever. It’s been said before, but thanks to Kasabian’s compelling array of talents, perhaps it has never felt sweeter.