Alt-J was formed in Bristol .
alt-J , stylized as ∆ , are an English indie rock band formed in 2007 in Leeds , by Gwil Sainsbury ( guitar/bass ) , Joe Newman ( guitar/lead vocals ) , Thom Sonny Green ( drums ) and Gus Unger-Hamilton ( keyboards/vocals ) .The band 's debut album An Awesome Wave was released in May 2012 in Europe and September 2012 in the United States , and won the 2012 British Mercury Prize .
Alt-J