There was a time during his five year hiatus, when you'd have been forgiven for thinking London-based singer/songwriter Barbarossa might not return to solo recording. So it comes as a rather pleasant surprise to get not one, but two releases of new material in the space of a year from the man behind the 'red beard' nom de plume - James Mathé.

Of course, it's not like Mathé wasn't busy during this extended break. When not touring with Jose Gonzalez or in Johnny Flynn's Sussex Wit he's plotted a solo sea change; overhauling his sound from acoustic folk troubadour to gloomy digitised soul man. Last year's Bloodlines traded the guitars of his debut - 2008's Chemical Campfires - for analogue synths and processed drums; Mathé's arresting vocals found their natural fit embedded amongst fresh landscapes of minimalist electronica.

And it's these foreboding electro-atmospherics which Mathé - in collaboration with Robert D Morris (better known under the pseudonym Boy 8 Bit) - seems intent on developing further on new EP Elevator, a lyrically spare collection of four songs that was initially conceived as part of the soundtrack to a short film. 'Elevator' - the most fully realised and conventional track here - opens the EP with a claustrophobic industrial thud; melodious synths panning and swirling around Mathé's haunted voice. "There is death behind your eyes/And a sign that reads vacancy inside" he broods before the song reveals itself in the chorus; resonant organs, widescreen strings and multi-layered vocals shuddering into life as they crack a veneer of calm.

'No Glue' and 'Lupo's Theme' walk a more experimental line, both sharing similarities in tone, density and rhythm. The latter sees Mathé's vocals modulated to the point of unintelligible distortion, a fluid bond to the central melody that shifts between octaves; thick layers of soul married to looping off-kilter beats that wax and wane across the track. And 'No Glue' is a sparse composition that highlights Mathé's lyrics; "Something in my eyes tonight, you don't recognise or like", he intones throughout the first half of the song, only to employ an almost imperceptible change in expression during the second half, which subtly shifts perspective, from accused to accuser/oblivious confusion to unnerving threat. 'Win/End' closes the album with fidgety hi-hats and cavernous beats; woozy melodies simmering gently under a swathe of warm chords. Mathé building pace incrementally as he recursively intones, "I want to win", until a falsetto synth finally pierces the gloom; its arpeggiated climax, like a pinhole of blinding light tearing through the dark.

If you were to find fault, it's that these songs feel too bound to the hangups of an unfilmed script. Where Bloodlines - which also drew influence from cinema - employed conceptual ideas to evoke emotional clarity, this EP meanders too much in a skittering ambiance that occasionally leaves songs feeling like sketches; evoking space and mood, but little else. Elevator is certainly not without its charms - Mathé's voice remains an instrument of fragile beauty - but next time it would be good to see him untangled entirely from conceptual trappings; for now however, just hearing him explore the boundaries and possibilities of his newly minted style is no bad thing.