To describe Ola Onabule as a sweet-voiced singer-songwriter from Lagos would be perfectly true, but it doesn't tell the whole story. It's like calling Ronnie Scott's a jazz club when in fact it is (and always has been) a Soho supper club, too. On the continuum between pure jazz and jazzy entertainment, Onabule veers more towards the latter.

His unique selling proposition is a golden voice, with a range and smoothness that recalls singers such as Luther Vandross and more recent pretenders to the soul-pop crown, such as Frank McComb and Van Hunt. Onabule could probably make a good living doing covers, but instead he has chosen to go his own way, with original material from albums such as In Emergency Brake Silence and The Devoured Man. He explains that the bossa-like How is about his "desperate struggle with existentialism", then deflates the introduction by saying, in his best crooner manner: "Hey baby, I know a whole lot more words like that!"

Despite the smooth-operator shtick, there is a gaucheness to his performance that is also quite charming. After reprimanding some diners for chatting during his soft soul ballad Back Home, there's an embarrassed pause that he breaks to say: "Sorry."

Onabule's five-piece backing group, though competent and well drilled, don't quite rise to the leader's ambitions. He has the potential to make his songs break free of funk, with a voice that is beautifully clear and appealingly textured, almost classical. There are moments when he lets fly with a kind of yodelling ululation, like a more radio-friendly Leon Thomas. Yet the elements - voice, songs, band, style - do not quite add up yet.

· At Swansea Grand Theatre tomorrow. Box office: 01792 475715. Then touring.