Muse, The O2, London Conor Maynard, The Dome, Brighton

The world’s loudest three-piece band give a blinding masterclass in how to fill the enormous spaces of rock’s thunderdomes

It’s a joy to watch Muse expand from lunacy to lunacy (Rex Features)

In the literal sense, as well as the hyperbolic, Muse are exceptional. Matt Bellamy, Chris Wolstenholme and Dominic Howard are the one band who treble-handedly justify the existence of the gaping, Luxembourg-sized thunderdomes in which, regrettably, rock now happens. They're the one band of whom no one but a madman would ever say they wished they could see them playing the intimate indie dives they toured a dozen years ago.

And they're back to tour The 2nd Law, an album whose unembarrassed pomp at times, makes Queen sound like Frank Sidebottom. It's a work that bends the listener to its will, and the new material can easily stand next to, say, the galloping Flashing Blade heroism of "Knights of Cydonia" and the quiet-to-loud, timid-to-terrifying set piece "Time Is Running Out".

In the past, the gold medal for my favourite Muse song has been a photo finish between two: "Supermassive Black Hole", essentially Prince reinventing "Kiss" on Judas Priest's rig; and "Plug-In Baby", on which a Hendrixed run at Bach's Toccata and Fugue in D-minor slams, head-first, into a turbocharged take-off of Air's "Sexy Boy", which in turn collides with a lung-bursting, vengeful chorus. This year, that pair have a challenger. "Survival", the official song of the London Olympics – ELO's "Mr Blue Sky" rewritten by Nietzsche, basically – may still be Muse's finest hour. Tonight, showing a rare glimpse of overt humour, Bellamy dedicates it to Bear Grylls.

It's a show that involves a hi-tech invertible Mayan temple (well, it is 2012) and more lasers than a George Lucas battle scene. Bellamy's stellar presence is rivalled by his bandmates, with bassist Wolstenholme venturing out on to the promontory for his lead vocal on "Save Me" and drummer Howard sporting a Mighty Morphin Power Rangers body suit.

Watching Muse expand and escalate from lunacy to lunacy is a never-ending joy. The day Muse shrivel, get small and do an acoustic tour will surely be the day the rock world itself shrinks to a white dwarf.

Ever since Cliff Richard was sold as the British Elvis Presley, there's been a long tradition of the UK manufacturing home-grown versions of North American stars. Conor Maynard, on that reckoning, may be the British Justin Bieber. Then again, maybe it makes him the 21st-century Cliff Richard.

Either way, someone's done a great job with Conor Maynard. At the start of 2012, the teenager from Brighton won the MTV Brand New award, beating the immeasurably more discussed Lana Del Rey into second place. He did so on the back of a series of YouTube videos in which he covered other people's songs. They supposedly went exponentially viral, with 50 million views before he'd even released anything, gaining him a rabid legion of fans (we're meant to call them "Mayniacs"), piquing the attention of the likes of Ne-Yo. Yep, someone's worked quite a number on this kid. If you're naive, you might even buy the idea that it's Maynard himself.

The perception that you're a viral success becomes a self-fulfilling prophecy: everyone wants in. So, debut single "Can't Say No", a reasonable slice of R&B pop reminiscent of early Justin Timberlake, went to No 2, and the album Contrast went one better. Something, though, doesn't add up.

Unlike the upsettingly pretty Bieber, at whose demographic he is being targeted, Maynard is not typical pin-up material. His is more of a geeky, boy-next-door look. He's more Harry Potter than Harry Styles. If Maynard were in Pretty in Pink, he'd be Duckie. In Happy Days, he'd be Potsie. In Gregory's Girl, he'd be Gregory. Nothing wrong with that, per se, but it does make the lust-crazed screams of the Mayniacs, and the pile of confiscated cardboard "We Love You!" signs in the foyer of the Dome, all the more baffling.

So, what else has he got? Awkward and knock-kneed onstage, he's no mover. He can sing, in the sense that there's never a bum note, but there's no tone or character to it. At X Factor he'd be unceremoniously weeded out at Boot Camp.

Maybe it's the songs, then. Maybe not. There's an old Steven Wright joke that goes: "I bought some powdered water, but I didn't know what to add." We've found the answer. Conor Maynard's songs are so wet I need to put my umbrella up indoors. And the sappy acoustic cover of Nicki Minaj's "Starships" fails to fly. If this is the future of the maynstream, things are gonna get arduous.

Next week

Simon follows Public Enemy's Paralympics-inspired revival and presses Alt-J to see what happens

Critic's choice

Swedish electropop heroine Robyn, above, takes a break from touring with Coldplay for a one-off show at London’s Brixton Academy (Thu), with support from Summer Camp. Also, horrorpunk/gothabilly noiseniks The Eighties Matchbox BLine Disaster reunite for Halloween shows at the Concorde 2, Brighton (Tue), and at the Electric Ballroom, London (Wed).