What's on: Monday Mar 26 Edinburgh Napier Composers" concert. St Giles" Cathedral, Royal Mile, 6pm, free, 0131-226 0673 Curtis Stigers Curtis Stigers is recognised as one of the world's leading jazz singers. With one of the most distinctive voices in music, the singer/saxophonist/songwriter pushes the boundaries of conventional performers and expands the jazz repertory creating modern standards. Curtis continues to blaze a path as one of his generation's finest and most original interpreters of modern songs. Queen's Hall, Clerk Street, 7.30pm, £25, 0131-668 2019 The Acoustidours John Hylton - Real Diamond Tribute to Neil Diamond.