Dream Theater

Octavarium (Atlantic)

Rating: 3.5 out of 5

When the ranking Chairmen of the American Prog Metal Institute start throwing pop melodies into their epic song structures, the band's diehard fans get nervous. Yet Petrucci's churning, downtuned riffs aren't foresaken here. (Neither, for that matter are Jordan Rudess's neoclassical keyboard musings.) As it happens, these pop textures actually push the guitarist to take some unexpected approaches. such as the pulsing intervals that make like a string section in ‘I Walk Beside You’ and the processed, psychedelic tones that kick off ‘Sacrificed Sons.’ But if it's finger-seizing picking you crave, the 16th-note riffing in ‘Never Enough’ and the leads embedded in the 24-minute title track ought to calm you down.

Moment of truth: ‘Panic Attack’ (5:20-6:12) After a typically astounding feat of speed picking in which both scales and arpeggios get royally worked, Petrucci embarks on a maelstrom of harmonies with Rudess.