Rachel Evans' previous release, the hugely well-received Seeping Through the Veil of Unconscious tape and LP, can in retrospect be seen as the culmination - and possible high water-mark - of a strain of hypnagogic pop involving ghostly (usually female) vocals intoned dreamily over muted guitar and piano melodies, the whole thing blanketed by layers of vinyl crackles and tape hiss. It's a formula that has delivered stunning results over the years, from Grouper to Inca Ore, but perhaps Evans realised that it was also one that could quickly become limited, a realisation that, on this eponymous album, sees her subtly change her approach to sonic mystery by embracing the synthesizer. No surprise then that Motion Sickness of Time Travel appears on Emerald John Elliott's Spectrum Spools imprint.

'The Dream' opens the album emphatically, building up layers of synthetic melodies and counter-melodies in the manner of vintage Tangerine Dream and Klaus Schulze, with a similar mastery of texture and atmosphere. And that's no exaggeration, I swear. 'The Dream' billows like a cloud, synth lines and noises piercing the ether like shards, similar in its intensity - if not volume and tempo - to Oneohtrix Point Never's opener to Returnal, 'Nil Admirari'. Like Daniel Lopatin on that album (released, in fact, through Spectrum Spools' parent label Editions Mego), Evans uses 'The Dream' to robustly shake off the shackles and influence of her previous material, delivering something that is more immediate and abrupt, albeit not as noisy. 'The Dream' is an ever-evolving, quasi-organic piece that develops like a suite, with various segments building up and then receding to make way for new passages that share the same abstract elegance of their predecessors, but are somehow different. A lot of recent synth acts, particularly those on Spectrum Spools, have channelled the spirit of Phaedra-era Tangerine Dream, but few have done so with the aplomb Motion Sickness of Time Travel (MSOTT from now on) does on 'The Dream'.

Which is not to say that MSOTT is purely an attempt to recapture the starry-eyed exploratory desire of those hippie futurists. Indeed, the first passage of 'The Dream' just as easily evokes the queasy, experimental and cosmic minimalism of Japan's Taj Mahal Travellers, and the piece is built in the manner of a prog-rock suite - imagine 'Tarkus' stripped of all its pompous lyrics and obvious imagery. Instead, each carefully balanced segment metamorphoses out of the dense textures that precede it, unfurling like limbs from a common abdomen. The title is well-chosen: like a real dream, the different moments of Evans' composition (for that is surely the word) don't always resemble, and often sit at odds with, one another, but somehow are part of a coherent whole. When she releases her tentative, oneiric, wordless moan into the mix, it doesn't seem out of place, but rather another ingredient in a well-defined, albeit unusual, sonic recipe.

The sense of meticulous balance that dominates 'The Dream' permeates MSOTT. The following three tracks, all equally long (the album lasts over an hour), all feature gently balanced sonic shifts relying on Evans' gradual integration of synth melodies and sequencer patterns, each one echoing some facet of former synth and kosmische greats like Manuel Gottsching, Emeralds or Cluster. If synth music is not your cup of tea, then MSOTT is not likely to change your mind, for its dedication to the futuristic and atmospheric capabilities of your average Korg or Moog is supreme. But the moment on second track 'The Center' - an altogether more immediate and direct piece than 'The Dream' - when the repetitive, looped melodies recede into the background and Evans' ghostly voice take centre-stage, obliquely intoning an indecisive mantra, is so filled with pathos and stark beauty that the whole album, synths, references and all, becomes crystalline. It's as if HAL from 2001: A Space Odyssey had paused in “his” torture of Keir Dullea and laid “his” synthetic eye(s) on a faded photograph of a long-dead family beaming in unison, Dead Poets Society-style. The contrast between technology and memory is acutely underlined on 'The Center' (and across MSOTT), as if Rachel Evans is herself fighting to find her voice in a world of machines and indifference.

So it doesn't really matter that the album's second half is a tad weaker than the first. What Evans has done is transposed her overtly emotional take on folk-pop into a realm of ever-evolving, ever-churning musical machinery. She snatches at Pauline Oliveros, Schulze and New Age, but as these different strands are processed and enhanced, her own voice (literally) emerges. A lot of modern synth and drone is derivative. Maybe Motion Sickness of Time Travel shows us how to do derivative properly, and beautifully.