It's not unusual for a band to offer standard and deluxe versions of an album on the day of release, although those extra tracks and "making of" DVDs usually come further down the line, when there's a whiff of having to fork out for something you've more or less bought already.

With Biffy Clyro's Opposites, however, it's the 20-track beast of a double album that feels like the essential purchase, not the 14-track single-disc edition.

That said, the half-dozen songs missing from the standard release are the very ones I'd have chosen myself as first against the wall. They're the tracks on which the Ayrshire trio most blatantly play the commercial card, where you can hear bits of Foo Fighters and Green Day (and even a wee bit of Snow Patrol) in the writing. Everything else across the 78 minutes here, however, bears the distinctive stamp of a Kilmarnock edition.

Six years ago, the move from the Beggars Banquet label and the release of Puzzle marked a game-changing moment for the band. A bolder template was set from the word go: album opener Living Is A Problem Because Everything Dies is an eccentric rock symphony that matches Metallica for jumps between time signatures and constituent parts. Two years after that, Only Revolutions also came at listeners from the leftfield, opening with mad sea shanty The Captain, with its horn parts, church organ and general big-top mentality.

Opposites contains its compositional eccentricities too, although you wouldn't realise it at first. The original idea of releasing two separate albums – The Sand At The Core Of Our Bones and The Land At The End Of Our Toes – lingers on in the split between Opposites' two discs. Sand, the band have stated, is the more lyrically bleak of the two, while Land casts a more positive eye on the future. Such distinctions are less obvious in the music, however: the outer edges of their style are not poles apart, more a case of shading into solidly mainstream or distinctively ambitious areas. When the arrangements break too many genre rules, they'll always pull back to safer ground with a massive anthemic chorus.

Across the running order of Disc One, the band seem sometimes in danger of dutifully acknowledging the wider fan base that looked their way when Matt Cardle won The X Factor with his When We Collide cover of Many Of Horror. Recent single Black Chandelier happily brings Simon Neil's accent back to Scottish soil after past transatlantic jaunts, and the jazzily syncopated rhythm of Sounds Like Balloons is very welcome. But, you start to wonder, is this new release simply consolidating past success and reassuring core listeners?

I'll admit I would have been disappointed if it had all ended here, but Disc Two gets under way with Stingin' Belle and Biffy at their most bravely bonkers, throwing in bagpipes and tubular bells; two songs later, the mood goes all mariachi with the cheeky trumpets of Spanish Radio. Trumpet Or Tap is as close as they've ever come to customising the blues, while the slow, bassy, prog-like synth foundation of Skylight could well be a nod to Muse.

Opposites picks up steam and doesn't flag. Yes, there's a tendency to throw an arm around a near neighbour for the security of a singalong chorus, but this is not rock music that churns and gurns: it plays around with complicated rhythms and difficult riffs then calms things down with great melodies and fist-in-the-air anthems. Biffy Clyro are restless for adventure but they're determined to bring a big audience along with them for the ride.

Opposites is released on 14th Floor Records/Warner Bros tomorrow