In a season marking 100 years of the Promenade Concerts, tonight's has a special significance. It is being given as a tribute to Sir Henry Wood, founder-conductor of the Proms, who died 50 years ago today. All four pieces being performed by the BBC Symphony Orchestra have special associations with Sir Henry, as the conductor, Andrew Davis, will explain from the platform. At the concert's heart is the Serenade to Music which Vaughan Williams wrote in 1938 to celebrate Wood's 50 years as a conductor. It features 166 outstanding soloists, tonight including Heather Harper, Yvonne Minton, Robert Tear and Thomas Allen.