Ellie Goulding may not be not a household name in America in the same star electro-pop universe that contains brand-name contemporaries such as Katy Perry, Lorde and Florence Welch. But if so, who wants to live in that house, anyway?

Ever since the anthemic, soft-EDM pop of 2010’s “Lights” and its accompanying folktronic album of the same name, the clarion-clear and haughtily emotive British soprano vocalist and songwriter has tested the boundaries of the usually chipper genre with mood-swing musicality. Along with busying her sonic palette with leaps in tremor and tone — from acoustic, gouache-like etherealism to happy stuttering house to maudlin ambient swish with a folk twist — Goulding has shown a willingness to experiment, ever so sneakily, beyond the clarity of her voice and its subtly rousing nature.

In this regard, “Brightest Blue” is more of a textural extension of 2012’s alluringly spacy “Halcyon” than it is her last, more mistily acoustic effort, 2015’s “Delirium.” Here, Goulding and her oddball collaborators take their catchy pop hooks — often elongated and pulled like taffy — and extend that reach into nu-soul, all while giving the singer-lyricist room to present a sad page-turner of a diary, torn pages, missed connections and all. With all that, the double album “Brightest Blue” may be Goulding’s best and most complete work, a lovelorn mess of emotions atop a mass of vibrant soundscapes masquerading as atmospheric R&B and strange, contagious pop.

“All I see is everything I’ve done called into question…. sorry what was the question?” sings an AutoTuned Goulding, rushing words like Drake, on the album’s first track, “Start.” While that cut is an airy mix of prepared pianos and stormy cloud sequences, it is Goulding’s voice, when mixed with that of the other-worldly avant-garde vocalist Serpentwithfeet, that is the stinger. After Goulding intones dramatic lines such as “You can’t begin to understand the magic she had before you killed her” with a sinister quiver, in comes Serpentwithfeet’s cranky falsetto for a match made in… frankly, it’s matchless. When the twosome finish “Start” together, before the background of a nerve-wracking rubber-band’s twang, they’ve set an impossibly high, weird bar for the rest of “Brightest Blue” to follow.

Yet Goulding manages, majestically, jumping from the lush, ’80s-synth-clap-filled “Power” to the aquatic house of “New Heights” to the swampy, churchy  soul of “Love I’m Given” to “Wine Drunk,” an “O Superwoman” rewrite if ever there was. “Ode to Myself,” a fragile, glacial ballad, thaws with the warmth of the tender, soulful melody and clear, teary singing. Save for blips of creaky strings and the occasional squeak, the breathy, piano-only “Woman” finds Goulding balled up tinier than a mouse and tighter than a fist, yet blossoming bigger and hotter than a burning bush. It’s the sortof anthem Will Ferrell makes fun of in that Netflix “Eurovision” comedy, only Goulding’s earnestness and the track’s sparse arrangement move “Woman” away from anything mawkish.

Capturing just the right words of sex, obsession, devotion and romance in a quavering soprano that moves from baby-dollish to bored to brooding gives Goulding a sense of theatricality several of her past albums lacked. Cohesion of storytelling. too, is another added plus on “Brightest Blue.”

If all that sounds magical and strange, we still haven’t gotten to the second album of the two: a five-song-long effort that continues the cranky textures of album one, but moves away from the mood swings and finds its heart in a juking, jiving, dance-pop place. Take “Worry About Me.” With its Blackbear collab and its soulful, impeccably syncopated phrasing (the staccato rhythm of lines such as “Baby, you don’t gotta, you don’t gotta worry / Worry ’bout me… / Been jumpin’ through hoops to get under you / But now I’m coo-coo-cool”), Goulding sounds like every member of TLC on hyper-drive. The plucked strings and elevated chorus of “Close To Me,” with guests Diplo and Swae Lee, is, in a word, adorable — the most infectious melody of a most infectious summer.

On a planet where other names in electro-pop may have greater recognition, “Brightest Blue” is the Ellie Goulding album that, from start to double-album finish, shows she’s as soulful, tight and mighty a brand as any.