Pet Shop Boys, Empress Ballroom, Blackpool<br/>Klaxons, Ruby Lounge, Manchester

A dash of wit, a slice of politics and a garnish of art-school style &ndash; the Pet Shop Boys' synth-pop formula just gets better and better

High season in Blackpool, and a steady drizzle dampens defeated spirits, while the illuminations flicker unwatched.

A British seaside resort in the rain is perhaps the perfect metaphor for Pet Shop Boys music – that exquisite mix of glitter and tears – and a certain "Every Day is Like Sunday" mood is fitting for a band who once described themselves as "The Smiths you can dance to", and whose first public utterance was: "Sometimes, you're better off dead."

Such juxtapositions are the duo's lifeblood. In their case, irony merely means being alive to the cruel echoes and mirror images that life throws up, and an appreciation of the Cosmic Joke. There's a purity of purpose, a clarity, even a sincerity (a word which, in his Bono-baiting days, might have horrified Neil Tennant), that has sustained them. Pet Shop Boys' heroic refusal to accept the built-in obsolescence of the pop group has paid off. In the face of their own scheduled irrelevance, they've kept calm and carried on.

This is the show, more or less, which by common consent slayed Glastonbury, and it fares even better in the gilded interior of the Empress Ballroom. Pet Shop Boys pioneered the idea of pop as theatre with their Derek Jarman-directed 1989 tour, and the later US jaunt, as documented in Pet Shop Boys Versus America. Sample quote: "The wigs are £1,000 each, and there's 34 wigs. And, there's a man to look after the wigs." To this day, a Pet Shop Boys show clearly involves wads of cash, but also a lot of ingenuity.

It's an imaginative mix of hi-tech and lo-tech, from LED to cardboard, from dancing skyscrapers to Gilbert & George-inspired projections on to a Lego-like edifice which, quite brilliantly, is then smashed like something out of Pink Floyd's The Wall. Neil and Chris themselves step out with Oxo cubes for heads, and will go through several costume changes.

At one point the dancers pretend to play keys and trumpets, reinforcing PSB's policy of never allowing "real" musicians on stage. Chris Lowe, behind a console, is left to his own devices. The pair's studied aloofness has loosened over the years. Tennant beaming "Hello Blackpool!" and leading the handclaps, local boy Lowe, one of the most celebrated Quiet Ones in pop, stepping out to dance in a mirrorball jacket. An extra effort has been made for this hometown show, from footage of the famous rollercoaster to the impromptu after-party on pedestrianised Birley Street.

One minor complaint: it's insanely quiet in the Ballroom. Afterwards I know I've seen the Pet Shop Boys, but I'm not sure that I've heard them. Then again, one wonders how many decibels they'd need to drown out a crowd who belt out "Heart" and "Always on My Mind" like they're national anthems.

"Go West" towers over Blackpool tonight, a classic act of détournement, the Village People's manifest-destiny hymn to the gay promised land of San Francisco made into a bittersweet commentary of the false dreams of the peoples of the communist bloc when the Berlin Wall came down. When Dusty de-pixellates on the big screen for "What Have I Done to Deserve This?", I'm not above admitting I welled up. They even manage to make me grudgingly concede that Coldplay's "Viva La Vida" is a great song by performing it as a medley with "Domino Dancing", although the same can't be said for the unscheduled orange-wigged encore of Dave Clark Five's "Glad All Over".

The new and newish material only proves how much Pet Shop Boys' consistent excellence is taken for granted. They've developed into astute observers of the political, as well as merely the personal. "If you've done nothing wrong you've got nothing to fear/If you've something to hide you shouldn't even be here," Tennant sings on "Integral", perfectly summarising the climate of paranoia and xenophobia in the post-9/11 West. On "Building a Wall" it's "There's nowhere to defect to any more..." Pet Shop Boys remain, in their own words, "sterile, immaculate, rational, perfect". All of those things, and none of them. They end with "West End Girls", which is exactly where they came in. They're among the immortals now. Pop of ages.

Nu rave is routinely dismissed as a media fabrication, but if you actually attended any shows by the main players, it was evidently a genuine, happening thing. The one band who were expected to have an afterlife, when the dayglo paint had been washed away and the glow-sticks tossed in the trashcan, were Klaxons. The classy, respectable, Ballard-quoting option, who actually won the Mercury prize with their debut Myths of the Near Future, they positioned themselves as an intellectual alternative, melodically as well as lyrically.

We're in the near future now, and the excitable 14- to 15-year-olds of 2007 are now 17 to 18 and probably looking for something a little cooler than Klaxons' ultra-violet aesthetic. At this low-key comeback gig, I spot just one couple in lurid orange face paint, looking a little lost. There's a definite whiff of "Does anyone care any more?" And, though I'm a fine one to talk, it doesn't help that singer Jamie Reynolds has eaten all the pies in the interim.

The jury's definitely out, but the excerpts from new album Surfing the Void make a solid case for Klaxons' continuing relevance, in particular the elegiac lead single "Echoes", and another which sounds like a cross between Joy Division's "Dead Souls" and Kate Bush's "Running Up That Hill", and Reynolds' knack with a Blur-like melody (and indeed his Albarnian falsetto) are present and correct. And, in the undiminished crowd-galvanising power of "Golden Skans" and "Atlantis to Interzone", they prove that it is, to invoke the old rave hit they've made their own, Not Over Yet.

Next Week:

Simon Price overdoses on electronic dance-pop at Groove Armada's Lovebox festival