Singer-songwriter PJ Harvey and unconventional Canadians DD/MM/YYYY are set to play on the Saturday (23 July) at ATP's I'll Be Your Mirror, scheduled for 23-24 July at Alexandra Palace, London.
Art rockers S.C.U.M. will play on Sunday (24 July), joining Swans, Beach House and Liars.
Other acts announced include Doom, Company Flow, Beak, Anika and The Passion Of Joan Arc.
I'll Be Your Mirror, named after The Velvet Underground's original ATP 7” single, is curated by All Tomorrow's Parties and Portishead, who headline both nights in their only scheduled UK shows of 2011.
Tickets are priced at £59 per day or £100 for the weekend.