Tool Summons the Thunder Clouds

Big rooms are rough on atmosphere. Even the most accomplished rock acts can find it hard to cope with all that space. But Tool is all about atmosphere, a gathering of gloom and thunder designed to rattle emotions near and far.

That was the sound the Los Angeles prog-metal quartet brought to the Forum on Monday, a bigger version of the same show Tool performed last year at the Wiltern Theatre. Some detail was inevitably lost in the larger setting, but the band made up for it with the size of its delivery.

Tool was all weight and intensity, by design a heavier package than the limber experimentation of opening act Tomahawk, a promising new band fronted by Mike Patton of Faith No More. Tool offered lumbering grooves and dark themes.

The concert began slowly, with a deep ambient pulse that led to Tool’s signature rock hit “Sober,” an intense study of desperation and release. And for more than 90 minutes Tool performed mostly in shadows, choosing the kind of anonymity that Pink Floyd once employed.

Singer Maynard James Keenan appeared to be covered in elaborate body paint. But most of the visuals were otherwise provided by a pair of screens, showing endless scenes of decay and dementia created by guitarist Adam Jones (also an accomplished special-effects artist). No image of the band itself ever appeared.

As unsettling as those images were, it was the music that cut the deepest, with Keenan picking up a guitar to add to the dark cascading patterns of “Schism,” a song from last year’s “Lateralus” album. It was mood music on an epic scale.