The Beach Boys, Royal Albert Hall

There they are! It's The Beach Boys! They're playing "Wouldn't It Be Nice", halfway through their second set of the evening and it blossoms with harmonic beauty, with pop's finest, most glorious ambition. Sure, in the shadows behind them there are a bunch of session musicians carrying them. Particularly in the first half those guys made damn sure there was such a wall of vocals it would be hard to detect any flaws in the ageing voices (mostly around 70) of the original Beach Boys.

Now, however, they're in their stride. They may be relics from another era but it's hard to over-estimate the importance of the Beach Boys in the history of pop. They will always be primarily associated with surf-crazed, squeaky clean, all American, pre-countercultural pop, but it’s worth remembering that all four Beatles – the biggest pop group ever - consistently acknowledged they would never have been pushed to the creative heights of Sergeant Pepper and their late Sixties work if it hadn’t been for constantly striving to better the extraordinary output of Beach Boys chief songwriter Brian Wilson.

Bruce Johnston, well, he's a Johnny-come-lately, only joined 47 years ago

Stage left, there he is at a grand piano, looking like a Beach buddha as much as a Beach Boy, with a rotund belly and impassive face that occasionally bursts into toddler-ish glee. And there's Mike Love, centre front, all in black and baseball cap, topped with a shiny gold jacket, slick, his school bully face unreadable. And there's Al Jardine, playing guitar, smaller than the rest and the most wizened. David Marks, clad in denim and American casual, shades, baseball cap, was in the original version of the Beach Boys - 50 years ago - but spent most of the following decades not in the group. Bruce Johnston, well, he's a Johnny-come-lately, only joined 47 years ago, and looking sprightly, in pastel shirt and effervescently toothy Hollywood grin.

Mike Love has long been regarded as the pantomime villain in the Beach Boys story, partly because of his rabidly unlovely right-wing politics and ruthless career pragmatism, but mostly because of the way he jeered at his already psychologically delicate cousin Brian Wilson’s mid-Sixties attempts, with the Pet Sounds and Smile albums, to push the Beach Boys sound to places pop music hadn’t ever been before. His subsequent dismissive attitude towards his one-time songwriting partner only seemed to confirm his odiousness and then earlier this week, without his bandmates' knowledge, he made a unilateral announcement that original Beach Boys Wilson, Jardine and Marks would be leaving the group once this 50^th Anniversary Tour finishes - and here’s the clincher – because otherwise it would affect the financial worth of the brand, which he owns. BOOOOOOO!!!

All of which adds up to the fact that this concert, and the one at Wembley tonight, may be the last ever by what’s left of the original Beach Boys, but these guys are pros and any animosity is left strictly to Twitter and newsfeeds. In front of the Albert Hall's packed, tiered audience, aged between approximately 30 and 70, Love tells us that the last time they played here was 17th December 1970 - "We'll have to get a bit more regular". The pre-interval half of the show is almost a warm-up - "Do It Again", "Hawaii", Wilson singing "Little Surfer Girl" in a frayed croon while the screen behind shows incongruous images of women who look like they'd be more at home in Loaded magazine than the sweetly retro Beach Boys universe.

New songs such as "Isn't It Time" are turned up louder but the first real spine-tingling moment is when Johnston - who wrote the deathless easy listening perennial "I Write The Songs", Love reminds us - sings us his lovely "Disney Girls". Then the show grabs us by the short'n'curlies, playing "Be True to Your School" as a montage of baby-faced Beach Boys shots flicker behind them. It's schmaltzy but it works, time is passing and that was long ago. They finish the first half with a feisty medley - "Little Deuce Coupe", "409" and, most fantastically, "I Get Around". What a song! The Ramones would never have existed without it and the like.

Any band that can hammer you in succession with 'Good Vibrations', 'California Girls', 'Help Me, Rhonda', and 'Surfin' USA' is inarguably fabulous

Part two is where they really pull out the stops. How many songs have they got? They start with "Pet Sounds" around the piano and by the time they reach the gorgeous "Heroes and Villains" it's clear their superb harmonic skills can, with some effort, be located. "Sloop John B" was never a favourite of mine - reminds me of primary school round-singing - but it pulls the Albert Hall to its feet and has real oomph. Their newie "That's Why God Made The Radio" fits neatly into the back catalogue and Wilson singing "In My Room" reminds again what a damaged talent he once was. In tribute to his fallen brothers they play two songs sung by them from the big screen, interweaving their own voices with Dennis and Carl Wilson. The former, who died in 1983, the only Beach Boy who actually ever had pop star looks, hairy and hunky, sings his delicious song from 1970, "Forever", while Carl, who died in 1998, gives us one of the greatest love songs ever written, "God Only Knows".

And then, well, then they slay us. Any band that can hammer you in succession with "Good Vibrations", "California Girls", "Help Me, Rhonda", and "Surfin' USA" is inarguably fabulous. They intersperse these with Chuck Berry's "Rock and Roll Music" and another cover, "Do You Wanna Dance", lathering on nostalgic black and white photos of days gone by, but it works a treat. This may be practically the same show, down to onstage patter, that they've been playing all year, and they may loathe each other in real life for all I know, but right here, right now, they seem glorious, they seem, creakily and with backing musicans taking the high notes, to capture a time when pop music was not background noise free in the ether but magically important. It is, of course, the calculated intention to muster these emotions but since they succeed lusciously, I'm inclined not to argue but to soak deep in it like everyone else.

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