The list, which aims to showcase the best new acts for the year ahead, was compiled using tips from 213 UK-based critics, broadcasters and bloggers.
Now in its 11th year, previous winners include Michael Kiwanuka, Jessie J, Adele, Mika, Ellie Goulding and Keane.
The Sound of 2013 longlist in alphabetical order:
Little Green Cars
Michael Kiwanuka was top of the Sound of 2012 list. The London troubadour sold 500,000 copies of his debut album Home Again around the world last year and was nominated for the Mercury Prize.
The other previous winners are: Jessie J (Sound of 2011), Ellie Goulding (Sound of 2010), Little Boots (Sound of 2009), Adele (Sound of 2008), Mika (Sound of 2007), Corinne Bailey Rae (Sound of 2006), The Bravery (Sound of 2005), Keane (Sound of 2004) and 50 Cent (Sound of 2003).
Other artists in the top five in previous years include Frank Ocean (Sound of 2012), The Vaccines (Sound of 2011), Marina and the Diamonds (Sound of 2010), Florence and the Machine (Sound of 2009), Foals (Sound of 2008) and Plan B (Sound of 2006).
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