It's every sad muso's favourite pastime to make that precious list of sure-fire classics. The kind of list that formed the cornerstone of that now almost anachronistic term, a "record collection". The classic album was its base material, and it always had to have certain qualities. If you want to get Nick Hornbyesque about it, it was a piece of work that defined an era, something hooked into the zeitgeist, yet also, paradoxically, something with a timeless quality. It also had to have a sense of unity, with each track complementing the next in terms of tone, mood, or a shared vision of the world. Of course at its simplest the classic should always have great songs, and as every muso knows the percentage of great songs on the album should be at least touching 95%, allowing of course for the token duff track.

OK Computer ticks a lot of the boxes required for certifiable masterpiece status. The generous critical reaction it received allowed Radiohead the implicit title of "most important band in the world". The album also had a stark unrelenting vision, buoyed up by some great music. However, making claims for it as an era defining album is tricky. Some commentators believe the album reflected a lot of unease about Blair's new Britain. All very nice and tidy as pop cultural theories go, but it's difficult to reconcile with an electorate happy enough to give Blair a landslide victory earlier that same year. As a collective expression of mass uncertainty it's rather unconvincing. In fact the whole "things can only get better" vibe was probably better exemplified by the excesses of Oasis, the rise of dance music, and Blair's 'Cool Britannia'.

If you want a truly epoch-defining album, then you have to go back another 10 years to 1987 and U2's sublime Joshua Tree. It's an album full of the singular virtues of the true classic. Ranging in theme across the globe, from El Salvador in the blistering 'Bullet the Blue Sky', to Africa in 'Where the Streets Have no Name', and back to Ballymun in 'Running to Stand Still' without missing a beat. With no blips, no creases, no awkward transitions, the Joshua Tree ties up a unique global vision with 11 flawless songs, each enhancing and resonating with the other. Like OK Computer, The Joshua Tree was also U2's conscious claim to greatness, and it propelled them upwards giving them a captive and entranced worldwide audience.

An unfortunate by-product of the album though was the gushing amount of purple prose used by various critics to describe it.

Rolling Stone saw "a vision of blasted hopes, pointless violence and anguish", but praise the lord, U2 were "not a band to surrender to defeatism". The album was burdened with all manner of redemptive messianic powers by drooling hacks. NME claimed it was "the sound of people confronting their own ghostsf It's the sound of people still trying, still looking, when all the world wants of them is volume and fireworks". All a bit much considering it was just an album showcasing some great songs. But therein lies the seductive power of the classic album, in its ability to make the muso wax lyrical, and where's the harm in expressing an enthusiasm, however hyperbolic?

And then it's back to 1967, to Sergeant Pepper's Lonely Hearts Club Band, and the Beatles' grasp of what really defines true greatness when it comes to sticking a dozen songs on to a piece of vinyl, namely, the defining value of ambition, and the urge to stretch one's creative sensibilities to the limit.

Using everything from the previously unthinkable idea of a twenty four piece orchestra on 'A Day in the Life', to blowing on official EMI toilet paper through a comb for 'Lovely Rita'. It was the rock and roll equivalent of the primal atom, with its evolutionary apogee in Radiohead's 1997 tour de force.

Looking back now over the intervening 10 years since OK Computer's release it's difficult to point to an album that defined an age, that grabbed it by the scruff of the neck with great songs, and gave it a good kicking. U2 tried to address the post 9/11 era with How to Dismantle an Atomic Bomb and came a cropper. Coldplay tried making their claim for greatest band on the planet with 2005's pathetic X and Y. Arcade Fire are currently undertaking a quest for world domination with their Neon Bible . . . and while it has been showered with superlatives, hindsight might still prove a harsh judge. In the meantime the miraculous might happen again, and the classic album may be resurrected by that unpredictable and irrepressible collision of ambition, blind luck, and rare genius.

Here's hoping those obituaries are premature.

FIVE ALBUMS THAT ALWAYS MAKE THE 'BEST OF' LISTS ASTRAL WEEKS Van Morrison (1968) A long long time ago, when dinosaurs ruled the earth, and Van Morrison was actually good he produced this classic, containing the joyous title track and the majestic nine minutes of 'Madame George'. Timeless.

WHAT'S GOING ON Marvin Gaye (1971) The first soul concept album, crammed with political, social and spiritual concerns about a world tinged by the shadow of Vietnam. All melded together by the soulful purity of a voice that just soars. Managing to be both cool and socially aware with tracks like the magnificent 'Inner City Blues'.

ACHTUNG BABY U2 (1991) U2 tap into the zeitgeist one final time to produce their last great album. Contains possibly the greatest U2 song ever, the dirty dark blasphemy that is 'Until the End of the World'.

AUTOMATIC FOR THE PEOPLE REM (1992) REM do what they do best and finish the most consistent run of fine albums in history, with a collection of songs about death that manages to be both melancholic and joyous. Album closer 'Find the River' sums it all up.

GRACELAND Paul Simon (1986) Paul Simon discovers the music of South Africa and marries it to some joyous pop, and even manages to make sickly sweet Linda Ronstadt sound bearable in the gorgeous 'Under African Skies'.