Three songs into Goldfrapp’s fifth album comes the refrain “Aaahh, feeling alive again,” built around a descending turnaround bolstered by a ecstatic up-down bass line. “Alive” sounds like disco Supertramp in the best senses of both, and like the rest of Head First, it’s swathed in an electronic chrysalis. Even when these songs are sweetened with real instruments—electric guitar here, piano there—they sound sleekly inorganic. Every part of them, that is, except for Alison Goldfrapp. Perhaps rejuvenated by her detour into electro-folk with 2008’s Seventh Tree, the singer bursts with life on Head First. Is it a return to form? Yes and no. Unlike the earlier work of the duo that bears her name, the album isn’t future-disco so much as state-of-the-art synth-pop. There’s a difference. One is imperious, alien, automated, synthetic; the other tends to be warmer, more open, emotional. It is, for lack of a better word, human. Even at its most clinical, as in the Kraftwerkian “Hunt,” Head First possesses a pulse underneath the plastic casing; when Goldfrapp sings of tumbling into love on the title track, there’s nothing stopping you from believing her. While previous albums occasionally displayed some heart, on Head First Goldfrapp wears hers proudly on her sleeve. Instrumentalist Will Gregory’s pulsing minor-key thrum on “Dreaming” recalls the inventively mechanical layers of synthesizer and drum machine that were the calling card of Vince Clarke: Just as Clarke held chilliness at bay by aligning himself with emotive singers like Alison Moyet and Andy Bell, Gregory coaxes a cool but soulful performance out of Goldfrapp. The result is like Kylie Minogue fronting Erasure. Equally strange (if compelling) bedfellows can be heard in “I Wanna Life,” which sounds like Kate Bush circa Hounds of Love hooking up with Imogen Heap. If there’s a price to pay for Goldfrapp’s new openness, it’s that nothing has the kick of earlier singles like “Ooh La La” or a “Satin Chic.” The closest Head First comes is on “Alive,” where Goldfrapp and Gregory are high not on the power of focused hedonism but on the giddy vulnerability of romance. It’s a fair trade, perhaps most sharply exemplified in “Voicething,” which closes the album. Wordless but not at all vocal-free as Goldfrapp flits in and out of Gregory’s bed of throbbing electronics, it simply cruises on its own luxuriousness for nearly five minutes. It’s not until the song’s almost over that you even realize there’s no percussion.