POP MUSIC: ROCK, COUNTRY, R&B;, RAP, LATIN, JAZZ : **, MINISTRY, “Filth Pig”, Warner Bros.

At one time, Ministry’s awe-inspiring, mechanized noise seemed to defy rock’s conventions the way a rocket does gravity. Now the duo slogs along like an old V-8 with a dragging tailpipe.

Though often regarded as an industrial-rock duo, Ministry has made its true contribution to hard rock: It basically reinvented metal in the late ‘80s via technology, beats and speed. But its sound was too raw to infiltrate the mainstream, and it became a source of vibrant ideas for more palatable/successful bands such as Nine Inch Nails.

After a four-year absence, Ministry is back with its most disappointing release since its embarrassing synth-pop days. Al Jourgensen and Paul Barker’s groundbreaking mixture of adrenalized beat, sampled layers and edgy, processed vocals has given way to dirge-like rhythms, basic, boring guitar riffs and silly, bellowing-monster vocals. The uneventful songs spill groggily into one another, and a muddled version of Dylan’s “Lay Lady Lay” doesn’t help matters.

Perhaps Ministry should do what other flailing rock bands do and look to its last three albums for a blast of inspiration.