Live soul music has always had its longueurs. Even when Sly Stone and Curtis Mayfield were at their height, there were no doubt self-indulgent moments when the audience's attention drifted.

Unfortunately for Joseph "Amp" Fiddler, such a moment comes within the first 10 minutes. "Brother James," he croons to his keyboardist, "tell them how you feel tonight." Brother James does so by means of a protracted solo. Then it's the turn of the bassist and the drummer to tell Fiddler, at length, how they feel tonight. Couldn't they just reply, "Fine, thanks"?

Fiddler, who's no slouch on the keyboards himself, is a veteran Detroit session musician for Prince and George Clinton. Clearly he picked up some style tips: he has sunglasses of Jackie Onassis proportions, a startled afro like a cartoon character with his finger in a plug socket, and a capacious smock that, to the untutored eye, resembles the jacket design for No 1 Ladies Detective Agency. He seems also to have contracted his former employers' weakness for tiresomely elongated funk workouts.

Naturally, the musicianship is faultless - Fiddler's band are as simpatico as quadruplets, and the bassist plays his instrument behind his head at one point, just because he can - but without material strong enough to anchor it, it's rather redundant. Fiddler writes jams rather than songs, with melodies so insubstantial that his attempt to initiate an audience singalong produces the kind of indistinct, half-hearted murmuring you get during hymns in a school assembly.

At least when the duelling keyboards squeal and shudder, Fiddler shrugs off some of his stifling debt to the 1970s and reminds you that Detroit is also the birthplace of techno. Even the occasional sonic flourish, however, is no substitute for charisma; after so many years playing second fiddle to outlandish frontmen, Fiddler lacks the presence to become one himself. He may sing like Sly Stone, he may play a little like Sly Stone but, senator, he's no Sly Stone.