By Michael Roddy LONDON (Reuters) - Songwriter and singer James Blake won the 2013 Barclaycard Mercury Prize for best album on Wednesday for "Overgrown", with the winner announced at the end of a star-packed concert and awards event in London. The album selected by a panel of music industry experts as the best of the year from British or Irish artists carries a 20,000-pound ($32,200) cash prize but more importantly helps to boost sales. Blake, 25 of London, who is known for his melancholy tunes but also incorporates hip hop and electropop, said as he collected his award on the stage of London's Roundhouse that he wanted to thank his fellow band members for "showing the importance of letting other people help you". Asked if he would give a description of his music, which many critics have had trouble characterizing, Blake said: "No, because that will come right back at me." Pressed on the point, he said that his music "...keeps changing so I keep writing new music." The shortlist in the award's 22nd year included some of the best-known names in the British pop world, including pop and fashion idol David Bowie who at age 66 was in the competition for "The Next Day" which won rave reviews from critics.