It's not every day someone comes up with a truly new, undeniably distinctive sound. Certainly not after several decades' worth of restlessly inventive, electronically aided aural explorers have canvassed seemingly every imaginable sonic and textural frontier in the broadly defined realms of ambient, experimental, and electro-acoustic art music. But that's exactly what Julianna Barwick has achieved; first with her 2006 album Sanguine, and even more boldly and assuredly on this release, which is billed as an EP even though its predecessor was equally concise. Barwick's arrival at such a refreshingly original sonic approach is in itself a remarkable feat; that the sound she's developed also happens to be instantly arresting and utterly beautiful is truly a cause for wonder. The sound in question, essentially the only thing we hear on the whole of Florine (with a few small exceptions), consists of a densely layered array of Barwick's own vocals -- murmuring alto hums; full-throated high-register vocalizing (usually wordless), and an even higher, unearthly siren's peals -- always heavily reverbed, and massaged to erase almost any trace of attack and to produce a long, lingering decay. The effect is a blurry, impossibly ephemeral build-up of sound that, despite its palpably human point of origin, feels neither natural nor artificial, but rather more elusive: supernatural, otherworldly, divine; strange and unfamiliar, and yet comforting and reassuring. Even without the apt, unmistakable imagery conjured by Florine's song titles -- "Sunlight, Heaven," "Cloudbank," "The Highest," "Anjos" ("Angels" in Portuguese) -- it would be hard to miss the fundamentally airy, celestial nature of this music, which has the billowing, pillowy softness of a cloud and a haunting, eerie beauty evocative of an angelic choir -- keeping in mind that angels are something decidedly other than human. There's a corresponding (if equally abstracted) spiritual quality to the loop-based, loosely structured compositions themselves: solemn and stately, at least at first, with simple (mantra- or hymn-like, perhaps) elusive melodic fragments repeated cyclically, gradually accreting density and sometimes near-rapturous volume, and then lapsing again into silence. Save for the interlude "Anjos," which swaps the typical all-but-a cappella model for a prominent instrumental undercarriage of glassine piano rills, these six tracks all take a largely similar form, but they create a considerable range of moods and effects via small variations in texture, harmony, and pacing. Florine may be brief, but it is in no way fragmentary or incomplete: this is a thorough, thoughtful, and mesmerizing fleshing-out of a potent and fascinating musical idea.