A raised eyebrow last week, when the new Earth album arrived, accompanied by a press release citing Pentangle, Fairport Convention and Tinariwen as key influences. It’s been a fair while, of course, since Dylan Carlson’s outfit made music quite so doomy and reductive as their reputation.

Nevertheless, folk-rock and Tuareg jams feel like they still might be a bit of a stretch, and so “Angels Of Darkness, Demons Of Light 1” proves. Much of the music in these five long tracks initially feels very much like a continuation of “The Bees Made Honey In The Lion’s Skull”, a sort of blasted Americana, more or less tectonic at the speed it evolves.

After a few listens, though, I’ve started spotting nuances in this gravity-heavy, hugely impressive music. Somewhere in the 12-odd minutes of “Father Midnight” emerges something of a jazz-tinged roll to the rhythm section, a brushed and high looseness underpinning Carlson’s still blackened riffing. A few years back, I came across the German doom-jazz band, Bohren Und Der Club Of Gore, evidently Earth fans. It now seems as if Carlson might just be a Bohren fan in return, given the monolithic swing that Earth – currently a quartet – are practising.

When I blogged about “The Bees Made Honey…”, I mentioned how Earth had belatedly moved into a grand tradition, that what was once unanchored noise-rock had grown backwards towards the blues. On “Angels Of Darkness”, that process seems even more advanced: as “Descent To The Zenith” unfolds, it’s not too far-fetched to suggest Earth have found a groove. It’s not one immediately comparable to that of Tinariwen, but a kindred sense of letting a serpentine groove work itself out, in its own time, driven by its own imperturbable forward motion, is not entirely dissimilar.

British folk-rock, however, remains harder to spot among the rubble. Lori Goldston’s cello comes very much into the foreground on the 20-minute closing title track, circling ponderously and reminding me very slightly of a Nick Drake track or two. For all the imprecations of doom in the language that Carlson uses for his music, though, “Angels Of Darkness…” feels serenely expansive; the work of a band heading inexorably, but extremely slowly, towards a kind of rock orthodoxy. Give Carlson another 20 years, and he might be tantalisingly close. In the meantime, though, the journey is remarkable – and hellishly hard, as an aside, to write about sentiently today.