It’s been described as the nearest thing the Belfast Festival has to a “fringe” – even though it takes place several months before the bigger event. The organisers of the Cathedral Quarter Arts Festival are pleased to be seen as somewhat on the edge – promising alternative venues and more experimental, even risqué artists. That’s not to says it’s obscure or totally divorced from the Arts Establishment – this May it’s managed to lure Sinead O’Connor to the city for the first time in twenty years. She’ll perform with the Ulster Orchestra in a free concert to be broadcast live on BBC Radio.