A glorious collage of musical artistry, drawing from darker regions than did any of its predecessors, it’s a work of extraordinary ambition, integrating aspects of Classical Greek tragedy, unorthodox religious imagery and some of the more jagged, acid-tinged pastoralism of drummer-vocalist Alex Neilson’s late 1960s psych-folk heroes the Incredible String Band.

Freighted with disparate ideas, the album convinces through its willingness to thrust forward without losing sight of a song’s considered structure, and also through insisting on a disciplined cohering of the elements. Thus, the swirling Farfisa sound in "Killing Time in London Fields" adds a decided rhythmic strength rather than providing merely colourful atmospherics. The band is determined to delve into a range of pasts, and if lead vocal Lavinia Blackwell sometimes calls to mind Grace Slick’s soaring flights of fancy, she does so without any affectation and always with an emphatic and appropriate sense of musical purpose.

That same stress on directed development, with impressively controlled and executed instrumental virtuosity, keeps The Sovereign Self far from any hint of formless experimentalism, and instead manages to convey details of a thoroughly justified journey well beyond the olde worlde Edenic with which they are often (inaccurately) associated. The fiercer than might be expected dialogue across the guitars at times almost threatens to pull the band into prog rock excess, but intelligent, well-timed shifts in direction maintain the freshness. Indeed, on "Bells of Burford" the multiplicity of sounds and changes in orientation are challenging but consistently engaging.

Demanding, uncompromising yet always musically convincing, the album veers thrillingly but never fully loses sight of the band’s more traditional territory. ‘The Singing Blood’, for instance, with its gorgeous harmonising, recalls some of the finest material on earlier albums like Carbeth. At other times, as on opener ‘Tween the Womb and the Tomb’, there are echoes of the Velvet Underground, with an uncompromising sound that summons up the spirit of John Cale’s electric viola. It’s a startling composition that gives a good indication of the range that is to follow. Spooky, serrated-edge ballads and disturbing tales of breakdown (relationship and psychological) are both unsettling and enthralling.

With lesser musicians, the diversity of styles and influences across time and territory might well have proven unwieldy and the results at best over-ambitious, at worst hopelessly diffuse. On The Sovereign Self, they combine to remarkable effect. This is not an easy record, but it needs to be heard. Again and again.