When the members of Metallica chose Bob Rock to produce the follow-up to their 1989 double platinum …And Justice For All, fans shuddered: the nation’s premier thrash band would be at the mercy of the hitmeister who had crafted sappy, radio-friendly anthems for Bon Jovi and Motley Crue. He would emasculate Metallica. Instead, Rock and the band have delivered the most sonically alive record in Metallica’s five-album history. Metallica bursts with rich, crunchy chords, hammer-through-glass cymbals, and soaring, crystalline solos. The subject matter is typically somber; guitarist/vocalist James Hetfield obliges his ominous baritone with tales of disillusionment and despair. Though his vocal efforts in “Nothing Else Matters,” the closest Metallica has come to an actual ballad, are awkward at times, his voice is frighteningly appropriate for “Of Wolf and Man.” “The Unforgiven” is a tragic lament in the tradition of “Fade To Black” and “One”: gentle acoustics suddenly give way to a brutal, full-blown assault. Metallica’s other standout is the lead single, “Enter Sandman,” a relentless one-riff tribute to the power of simplicity. Though Metallica is not without unspectacular moments, the musicians and their producer have created an intense piece of rock.