With a new album, Tide, just out (and also available on fascinatingly clear vinyl, as I spotted in the foyer), a feature on Lauren Laverne's 6Music show, and a German tour just finished last month, this group seems justifiably set for great things.

Critics always seem to say of Wooden Arms how difficult they are to describe, which used to annoy me until it came to writing my own review. How (and whether) to pigeonhole the ambient yet exciting combination of classical and indie-folk sensibilities? Their sound combines heart-wrenching vocal harmonies, soothing rhythmical cello and violin, melodious piano, guitar and a couple of trumpet solos... Maybe it's best to leave description to them: "Wooden Arms is an alternative chamber music band from Norwich, featuring choral elements: a distinctive yet delicate blend of classical instrumentation meets modern melody". There we go.

J2 was a lovely space for this gig: theatre-like, laid out with full seating and notably beautiful stage lighting, it played host to a mixed crowd – I spotted students, middle agers, young lovers in the back row, and even a couple of solo old men – which must be a testament to Wooden Arms' ageless appeal. Unexpectedly brilliant support came from Gaze is Ghost, a girl doing things to melody and piano the likes of which I haven't seen since Regina Spektor, and Tom Adams, who won over the room with a combination of amiable goofiness and masterful musicianship. With hands skipping over innumerable buttons and knobs he sampled, distorted and layered his voice, creating an audacious sonic backdrop to songs that were sometimes almost James Blake, sometimes more James Vincent McMorrow. Not even a McAfee computer security warning sign popping up over the projected visuals could diminish our enjoyment.

Wooden Arms' set opened with 'Prelude' and 'Charicla', the opening pair on their eponymous 2013 EP; these segued into one another smoothly, establishing the mood and bringing us to the level of alert relaxation their music tends to invoke. Subsequent high points included the wonderfully delicate new title track, 'Tide', and 'Carried Away', a moment of more obvious structure that re-focused our attention within the occasionally amorphous sound. Haunting vocals and a compelling drum riff made 'December' a hit, and the group rounded off the night with 'Burial', a very new song which, with its unexpectedly punchy finish, left me excited for new directions this astoundingly talented group of musicians might be exploring next.

Wooden Arms will be appearing at St Pancras Old Church, London, on 17th October

www.woodenarms.co.uk