Delerium's Bill Leeb and Rhys Fulber have been perfecting their Enigma-esque form of pseudospirtual, vaguely gothic dance pop since they began collaborating in the mid-1980s. Whether working as Delerium, or under their better-known name Front Line Assembly (among others), their music, which is airy and laden with reverb, usually features guest contributions from a rolling ensemble of female vocalists.