'The Voice's Christina Aguilera, Adam Levine, Cee Lo Green and Blake Shelton rock House of Blues

Slideshow posted in Photos | Friday, November 09, 2012

1 of 14: Clockwise from top left: 'The Voice' coaches Cee Lo Green, Christina Aguilera, Adam Levine and Blake Shelton appear at the House of Blues in Los Angeles on Nov. 8, 2012 for the NBC show's special concert to celebrate the announcement of the top 12. ( Photo / Frazer Harrison / NBC)