The extraordinary rise of The Unthanks could not have been easily predicted. Now known for their amalgamation of traditional folk music with a contemporary sound, the sisters Rachel and Becky (who originally went out under the name Rachel Unthank and the Winterset) were at the outset an almost purely traditional folk outfit, re-arranging and covering songs written by persons unknowns, and largely steeped in the history of Northumbria. Their debut album Cruel Sister displayed their tremendous abilities and passion and was eventually awarded Folk Album of the Year by Mojo.

But they weren't going to forsake the rich tapestry of music from their upbringing and elsewhere. Nestled amongst the pure folk songs of Cruel Sister was a cover of Nick Drake's River Man, a choice of music that highlighted the fact that the sisters, along with long-time producer (and husband to Rachel Unthank) Adrian McNally, were interested in music that didn't just pander to the purity of folk music, but wished to branch out and include the sisters love of all kinds of modern music. Subsequent album The Bairns, whilst still steeped in traditional music, had a cinematic quality that was timeless, and became a bigger commercial success than the debut. The word was out; audiences that weren't necessarily folk aficionados or lovers, started to check out these wonderful singers, and performers; siblings, who despite their seven year age gap, could sing in perfect unison, their distinctive voices telepathically complimenting each other and imbibing their chosen material with a deep, yet mesmerising sadness and melancholy. The fact that they indulged in a bit of clog dancing on stage, helped their cause further, entrancing audiences, many in love with their youthful enthusiasm, genuine warmth and understated ability. They were riding the wave of the folk revival movement set off in the late 90s and early noughties (see Eliza Carthy, Seth Lakeman, Kate Rusby et al), a period when British folk music became to be widely recognised as a vital and integral part of social history, and didn't necessarily involve the age-old parody of a singer with a finger in their ear…

Roll on to 2015, and after a four year gap, The Unthanks have a new studio, and a new album (although they have, in the meantime, released three albums – issued as the Diversions series – recordings that are based on other peoples songs such as Robert Wyatt and Anthony & The Johnsons, and re-workings of their own material with the likes of the Brighouse and Rastrick Brass Band), and a tour of the UK, taking in Brighton's Dome once again.

Mount The Air will no doubt receive even more attention, and more sales, than their previous album. And it's easy to see why. The lead and title track is up there with some of the The Unthanks best… trumpet, strings, a tinkling drum, and piano inch their way slowly forward, before a voice: 'I'll mount the air on swallow's wings, to find my dearest dear', the first of many winged references throughout the album, as the song swoops and soars, the lyrics and music reminding me of the Brigg's classic animation, The Snowman. It's certainly an epic, clocking in at over 10 minutes, and is built around the mournful tones of the lone trumpet of Tom Arthurs. This is largely Adrian McNally's composition, a marrying of folk voices and a jazz meets classical soundscape, that shifts gear subtly throughout. Based on the themes of a one-verse traditional ditty, found in a book of Dorset songs in Cecil Sharp House by Becky Unthank,  as is much of the material on the album, Mount The Air – the song as well as music of the rest of the album – is very much a band effort, the sisters, McNally, and the various players expanding the original words into what is, in effect, an original composition.

Madam, like most of the material here, begins with a simple piano before all the other elements are brought together – brass and strings in the main – the gorgeous melody of the song equally complimented by the sorrowful sounds, given plenty of scope to paint the picture, before just an elegant piano closes it out. 'The maiden walking in her garden, but her name I do not know/I'll go court her for her beauty, let the answer be yes or no… Madam, madam I came a-courting, that your favour I may gain'. It may be fairly bog standard trad folk lyricism, but like all great music, the sentiments resonate timelessly, and with the intimate, yet ambitious, music created by McNally and a high calibre band of musicians, it flows beautifully.

Elsewhere, Flutter – an original song written by Becky Unthank – has a distinctively Portishead/trip-hop vibe, thanks to the moody electric piano and gentle bass beat, while the constant vocal refrain of 'Life's A Flutter' tracks the shifting chord sequence. And the birds theme continues, to the point where even a sample of a winged bird begins the Nursery rhymesque Magpie, only voices along with the underlying harmonium drone, the only instrument throughout, bar the occasional distant drum beat and crescendoing cymbals, as the sisters hark back to their traditional folk roots, the voices up close, the in-takes of breath really bringing this beautiful and dramatic song to life.

Then it's back to the theatrical orchestral pop of the epic and glacial Foundling, nearly 11 minutes long, written by McNally, the sisters again alternating vocal duties, as mother and child, telling the story of a refuge (the real-life Foundling Museum in London tells the story of the Foundling Hospital, Britain's first home for abandoned children). Piano and strings wring it out for all its worth, the song becoming meditative in quality, before trumpet edges in for an extended and expansive instrumental passage that builds and builds. It's perhaps at this point that McNally and co could have called time, the final verse extending the sorrowful sentiments perhaps a little too far…

Last Lullaby – again, violin, piano (a repeating refrain, from beginning to end), drums and trumpet – comes to life when lyrics, a mix of the traditional with original words by Rachel, entrance and sooth. Again, the song features long instrumental passages between verses, the song gently swelling and waning towards the end, perhaps in line with the sleeping and dreaming child…

Hawthorn – 'Hawthorn white, hawthorn red, hanging in the garden at my head. tell me simple, tell me true, when winter comes, what will I do. I have a house with chimneys four. I have a silver bell at my door' – again features a winged bird (metaphorically and earth-bound) within the tale; the simplistic bareness of the lyrics, complimented by a minimalist musical palette, which once again consists of sparse piano and mournful trumpet, signifying the changing seasons. Unremittingly sorrowful, its a little too close to some of the other material here to really stand out.

For Dad presents a welcome change of tack, featuring a drone and an old recording, I can only presume, of one of the Unthanks, as a toddler, from 1978. 'What have you got to say to that microphone'? asks Dad, before this instrumental homage – just violin and harmonium – paints a picture, somewhat dark and haunting, but emotive nonetheless.

The relatively straight forward, and faintly jaunty, The Poor Stranger, a song collected by Cecil Sharp from a singer in North Carolina, is centred around McNally's piano, and Rachel's voice, warning against the perils of charming men. It might have been an appropriate way to end the album, but McNally cannot resist a final instrumental song, Waiting, that while a spirited little gem in itself – it's repetitive folk-meets-classical refrain reminiscent of Penguin Cafe Orchestra – is a little superfluous, the album now clocking in at over 60 minutes, long by the standards of 2015.

The Unthanks say Mount The Air is an invitation to be free and weightless, to transcend reality, and enter your imagination. It certainly can, given the right mood, take you to places only music can, the unpredictable metaphorical winds taking you on a journey, both spiritual and earthy. An almost invariably classy album throughout.

Jeff Hemmings

Website: the-unthanks.com
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