alt-J (also known as ∆) is an English indie rock band formed in 2007 in Leeds, England, by Gwil Sainsbury (guitar/bass), Joe Newman (guitar/lead vocals), Gus Unger-Hamilton (keyboards/vocals) and Thom Green (drums). Their debut album An Awesome Wave was released in May 2012 in Europe and September 2012 in the United States, and won the 2012 British Barclaycard Mercury Prize. Gwil Sainsbury amicably departed the band in early 2014. Their second album This Is All Yours is slated for release on 22 September 2014. As a replacement for Sainsbury, Cameron Knight will be a support member for alt-J's live shows, playing guitar, bass and sampler.