Martha Wainwright @ George Square Theatre

Martha Wainwright makes music that is difficult to verbalise justly. It's a humbling reminder that music is a language of its own. Her songs are bright and colourful self-portraits: her style painterly, lyrics often abstract. Her voice is dark brown and her hair is light blonde. Her guitar is a regular six steel-strung semi-acoustic, yet she plays it like it has twelve. Her voice trills over sometimes three octaves in one breath without breaking a note. She sings songs that mix light humour with dark emotion without pretension or dilution.

Suitable precedents could hint at Janis Joplin, Joni Mitchell and Eva Cassidy, though comparisons to fellow female songwriters of generations past and present might masquerade her particular freshness. Her sound has a nostalgic quality, reaching back to some place she's barely old enough to have been. Surely, some of this talent is borne of the Wainwright lineage.

Martha's own gift is the warmth of her voice and personality that shines through her songs and live performance. "This is the part when I'm supposed to plug the merchandise…" she jokes as she somehow retunes her guitar to some obscure key. This is folk, but by no means the twee, tweedy or outmoded kind with a hackneyed drawl. This folk, is the new black.