Japan’s Boris and Los Angeles’s sunn0))) currently stand at the foreground of the doom-metal underground. Such recognition couldn’t happen to two nicer bands that make unearthly sludge.

For more than a decade Boris and sunn0))) toiled in easily stereotyped independent metal, where band names sound like punch lines to bad Viking jokes, logos are rendered in fonts that resemble epileptic mandrill designs, and bands themselves wear more makeup than the Blue Man Group. But ever since the 1998 formation of the Southern Lord record label, which embraced the stereotypes and took its bands and their music seriously, extremely slow and heavy rock has been reinvented as an innovative and experimental force. Boris and sunn0))), two Southern Lord titans, howl at the Avalon tonight.

This rebirth was a long time coming. By the early 2000s, sales attrition and aging members did away with many 1990s bands that were weird, loud, visceral, and, well, dangerous. Noise-rock abandoned rock in favor of circuit board bending and power-electronics noise. American indie-punk rediscovered the dance floor. Experimental drone bands stopped shaving and chased winsome, elfin young folkies into the woods. Hardcore discovered LiveJournal and sprouted various emo-cores. Indie-rock bands combined their love for cool clothes and postpunk. And once a generation’s jeans are fashionably tightened, head-banging becomes passe.

Fortunately Boris never witnessed such changes first hand. The trio formed in the early 1990s – its members are known only by their given names: Atsuo (drummer/vocalist), Takeshi (bassist), and Wata (bassist) – in Tokyo, a city host to other volume sculptors such as Haino Keiji, Masonna, and Merzbow, all of whom Boris collaborated with over the years. Cribbing its name from the lead track from the Melvins’s 1991 album “Bullhead,” Boris took that song’s running-in-a-swimming pool feeling and turned it into a road map of adventures in tempo, volume, and riff-making.

Exploration permeates Boris’s output. Its 1996 album “Absolutego” unleashed a single, hour-long slab of distortion ooze and rhythmic buildup. A slightly more psychedelic streak peppers 1998’s “Amplifier Worship,” as if the trio had just heard Blue Cheer for the first time, while 2002’s “Heavy Rocks” married the swirling guitar paisleys of “Amplifier Worship” to a Stooges-raw forward thrust. Listening to these records makes two things clear: Mission of Burma’s Peter Prescott and Boris’s Atsuo are the only two living singing drummers who matter and guitarist Wata is an impressive talent.

Onstage, the petite guitarist is dwarfed by her amplifier stack; the Gibson Les Paul strapped over her shoulder covers up most of her torso. She plays with an almost expressionless poise, as if she could be watching a day-time talk show. And without ever appearing to break a sweat, she cranks out top-notch serrated riffs, wide-bodied distortion, echoing feedback, and screaming solos.

The full scope of her ideas comes to the fore of Boris’s most widely heard albums in America, 2003’s “Akuma No Uta” and 2005’s “Pink” – its most recent, and its most accessible, release. “Pink” offers something of a tour of metal and psychedelia sound; beginning with the atmospheric jam “Farewell” and the full-throttle guitar workouts such as “Woman on the Screen” and “Nothing Special” it moves on into feedback noise with “Blackout” before winding back through garage rock and settling into the reverberating space-rock of the ten-minute closer “Just Abandoned Myself.”

sunn0))) takes heavy music in the extreme opposite direction. The duo of Southern Lord label co-founders and guitarists Stephen O’Malley and Greg Anderson makes excruciatingly slow, almost flat-lined drones that sound like what barely audible ambient outfits such as the Orb, the KLF, and Pole would create if they grew up with as much Black Sabbath and Saint Vitus as Brian Eno and Soft Machine.

Since debuting as an Earth tribute band with 2000’s “00 Void,” O’Malley and Anderson have perfected a taut balance of extended doom – sunn0))) songs typically reach the 10 minute mark and sometimes inch toward 30 minutes – and self-aware, cheeky wit. Which is not to say that sunn0))) is a joke. Its amplifier buzz, whose hum must be heard at high volumes in order to recognize the slight changes in feedback tones, is a subtle craft.

O’Malley and Anderson recognize the narrow niche market of doom metal; they embrace the nebbish stereotypes and turn them into badges of honor. The duo performs in monk-like hooded robes and stand stock-still in front of a wall of amplifiers while a smoke machine clouds the stage. It’s admittedly absurd, but the hypnotic, amorphous sea of crackling, shimmering notes sunn0))) creates with guitars and electronics has an eerily inviting result – as impossible to escape from as quicksand.

Boris and sunn0))) will perform tonight at 8:30 p.m. at Avalon (47 W. 20th Street, between Fifth and Sixth Avenues, 212-807-7780).