After spending 16 years as the singer/guitarist in the Icelandic group Sigur Rós, Jon Thor Birgisson renamed himself Jónsi and began a solo career. Though he had used the name before on a project with Alex Somers (as Jónsi & Alex on 2009's album Riceboy Sleeps), the pixie-voiced singer's first solo album under the Jónsi name was Go, which was released on longtime label XL in the spring of 2010. Featuring more upbeat and poppy songs than those he had written and sung with Sigur Rós, Jónsi was joined on the album by Somers, modern composer/arranger Nico Muhly, and Samuli Kosmine...