The concert hall may have no more genuinely post-modern experience to offer than a Shirley Bassey show, Richard Williams writes. For her audience, the only point is to participate in as many standing ovations as possible. At the Royal Festival Hall last Tuesday, during her 40th anniversary tour, every other song stopped the show, none more tumultuously than an interminable arrangement of Foreigner's 'I Want to Know What Love is' so slow and thunderous that Phil Spector would have been proud to own it. But apart from a remarkable gown that artfully exposed her wondrously sculpted back, nothing fitted her better than a piece of continental kitsch called 'Dio, come ti amo', which seemed - like the singer - to have been cryogenically frozen in about 1959. If she needed a redeeming feature, it would be a self-awareness which gently mocks both her worshippers and herself.