There's always a few techno-geeks salivating over the equipment, but the rest of us couldn't tell an Akai from a Kawasaki and are too busy dancing to care either way. Which is why the first live performance by Underworld as a duo, at this week's 10th birthday party for their record label Junior Boy's Own, was as exciting as any they gave with founder member Darren Emerson, who recently quit the band to concentrate on his DJing career. Emerson's input will be missed when they go back in the studio, but there was nothing noticeably missing from Underworld's music when Karl Hyde and Rick Smith played it without him. It's an indisputable but rarely acknowledged fact that most people at a live performance of electronic music won't have any idea what the musicians are actually doing on stage, or which aspects of the music they each contribute. There's always a few techno-geeks salivating over the equipment, but the rest of us couldn't tell an Akai from a Kawasaki and are too busy dancing to care either way. Which is why the first live performance by Underworld as a duo, at this week's 10th birthday party for their record label Junior Boy's Own, was as exciting as any they gave with founder member Darren Emerson, who recently quit the band to concentrate on his DJing career.

Emerson's input will be missed when they go back in the studio, but there was nothing noticeably missing from Underworld's music when Karl Hyde and Rick Smith played it without him. The focal point of Underworld's live show has always been Hyde anyway. He flicks the odd switch, intermittently plays guitar and, of course, delivers all those surreal cut-up, partially improvised lyrics But far more importantly, he dances like a lunatic. It starts in his hips, like he's resisting possession by the spirit of Elvis. It spreads upwards through his body and, as the music builds, his arms begin to flail.

Then, all of a sudden, he's off, sliding around the stage like a child on rollerskates after too many E-numbers It's utterly unique, unaffected and irresistible. Even if the music wasn't fantastic, he'd still have half the audience grinning and dancing along with him.The music was fantastic though. Tougher, more insistent and, of course, much, much louder that it is on record, it still had all those subtle distinctive little details to counterpoint the simplicity of their rhythms. Underworld's understanding of what makes people dance is innate and instinctive, so that what they want to play tends to coincide with what the audience want to hear - which you'd think was common to all performers, but unfortunately isn't. They played their very best material - that is, a couple from their first and third albums and almost all of their masterpiece, the Second Toughest in the Infants album Oh, and "Born Slippy" of course. Before the opening chord of that anthem finished reverberating, every hand in the sold-out venue shot into the air.

I fear that at this point, unable to see for the sweat running into my eyes, my critical faculties may have been dulled. I was sure of only two things - I have one of the best jobs in the world, and Underworld are still one of the most exciting live acts around.In 1992 the Utah Saints proclaimed their arrival with the Kate Bush sampling "Something Good" and its rousing chorus of "Utah Saints, Utah Saints, U-U-U-Utah Saints". They pioneered the dance/pop/rock crossover, devised a way to play dance music live and toured America. Eight years after their last release they're back, and those shows in America must have been something special because soul legend Edwin Starr collaborated on their recent single "Funky Music" and their second album, due in September, includes vocal contributions (not samples) from Iggy Pop, Chuck D, Chrissie Hynde and REM's Michael Stipe.But if you're worried that hanging out with such superstars may have changed them, fear not. Jez Willis sports that same Mohican and he and his band still favour the army surplus sartorial style that was briefly fashionable back in 1992.