Ever since releasing their astonishingly good Stand Up for Your Mother debut back in ’02, Vancouver’s Young & Sexy have struggled to make music that’s airy and sweet without being precious, charming without being twee. It’s a challenging endeavour, since Y&S’ core elements — the refined, sunny harmonies of Paul Hixon Pittman and Lucy Brain, and shimmery guitar chords that gently rise and fall, strung out like telephone wires — lend themselves to pillowy, formless compositions that, while pretty, occasionally veer toward easy listening territory. The quintet take some risks on The Arc, mixing up their customary dream pop with slightly proggy Floydian poperatics — on tracks like “Young & Sexy VS The Arc” and “Demon Dreaming,” Hixon Pittman and co. borrow the language of gothic fantasies, with guitar lines that distort and sour at the edges and rumbling percussion. It’s weird (think Isobel Campbell cooing about elixirs, chalices and “skewering his muse”), but intriguing. The best track here, though, is “The Poisoned Cup,” a lovely blue-eyed soul number that may or may not be about religious extremists.