It has been a year since Ellie Goulding released her second album, Halcyon, time mostly spent touring it across Europe and the US. You'd think her set would be polished to perfection by now; instead, it's a disjointed thing, its lack of cohesion suggesting a singer admirably determined to resist conformity, but also uncertain as to the kind of singer she wants to be. Is she a dancefloor diva, an earnest balladeer, a hair-thrashing rocker? Goulding enacts them all in sequence across the set, as well as within the brief span of individual songs.

When it works, such as in the transition of Joy from piano ballad to storm of synths and celebratory drums, her mutability feels vibrant and attractive. But too often you detect a blandness in Goulding's guises that strips them of genuine character. There's too much vague head-banging and not enough visceral pounding at the drum that stands beside her; too much generic body-grinding amid the excitable, girlish bouncing; too much forced emotion in her ballads, making them leaden instead of delicate. It's as if she loses herself between doing what she wants and what she thinks a singer like her ought to do.

Odder still, for a woman with a filigree voice that floats up to soprano heights, Goulding is chary of letting her vocals dominate. In Don't Say a Word, her voice is buried in the mix, almost drowned by the drums; in Under the Sheets, it is so distorted by effects that she sounds like a broken modem; in I Need Your Love, the recorded backing vocal silences the live voice altogether. This tinny electronic choir is distractingly present throughout – but if there's a barely audible harp on stage, and a string trio, why not an additional singer? It's just one of many aspects of Goulding that don't add up.

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