LFO were a British electronic music act on the Warp Records label. LFO were pioneers of the bass-heavy techno, IDM, and acid house music of the late 1980s to mid-1990s. Originally, the group was composed of Gez Varley (born 1971) and Mark Bell. (1971–2014) After Varley left in 1996, LFO was Bell alone. Bell died in October 2014.