Certain underground-rock compilation albums are intended to be more than just a bunch of songs or a label sampler — they’re attempts to document a scene, or a particular æsthetic moment. A carefully assembled, properly sequenced compilation can be better than any album most of its contributors will ever make. The legendary Wanna Buy a Bridge? comp epitomized the British art-punk generation of 1980-’81; 10 years later, Kill Rock Stars launched the label of the same name and crystallized the Pacific Northwest/DC indie-rock generation. No New York, Flex Your Head, Me Want Breakfast . . . sometimes it’s hard to tell whether a scene created a compilation or vice versa.

Mike Simonetti, who runs the New Jersey punk label Troubleman Unlimited, assembled the new collection Troubleman Mix-Tape to have the same sort of effect as those classic comps. Begun in 1997 and promised often enough since to have become a running punk-world joke, it has finally appeared, and it is massive: 52 tracks by 49 bands on two CDs. If it lived up to expectations, it’d be one of the greatest compilations of its kind ever. It doesn’t, unfortunately, though it’s pretty intriguing anyway.

The biggest problem with Troubleman Mix-Tape is the scope of its æsthetic. Simonetti has his eye on nothing less than the American DIY rock scene in its entirety (with cameo appearances by a few foreigners, like Japan’s Melt-Banana and England’s Red Monkey). That’s too broad an aim to produce any sort of formal consistency, but not broad enough for the result to function like a real mix tape, where stylistic contrast is important. Too many bands contributed throwaway instrumentals or inferior alternate versions; there’s too much crummily produced screamy emo by bands who’ve just figured out that " bleeding eyes " and " fucking lies " rhyme. (And the first pressing is marred by a horribly muted mastering job; the second will, it’s reported, be much clearer-sounding.)

Even so, TMT says a lot about what is going on in this country’s electric underground. There’s a strain of bands who build on the sour funk-punk hybrids of 20 years ago (!!!, Out Hud, the Turn-Offs, Glass Candy and the Shattered Theatre, Pixeltan), and they’ve got some of the most impressive stuff here. There’s a sort of organized-seizure school who rev up the complicated counting games of progressive rock into ultra-distorted high-speed spasms (Lightning Bolt, Black Dice, Pink & Brown, Touchdown). There’s a lot of free-floating aggression of the kind you have to see live to " get, " and more distinct flavors of near-inchoate guitar/bass/drum noise than you’d ever have imagined possible. And there’s very little that acts much like songs in the traditional verse-riff-melody sense, commercial rock having repossessed most variations on that form for its own purposes.

Two of the best bands on TMT have recently released albums of their own on Troubleman. Red Monkey’s Gunpowder, Treason and Plot (the title’s from an old rhyme about Guy Fawkes) has the urgent force of a debut record by a band with a point they’re intent on making. In fact, not only is it not their first album, but bassist/singer Rachel and guitarist/singer Pete have been working together for about 10 years now going back to their shambolic early-’90s duo Avocado Baby and the now-defunct label Slampt that they ran at home in Newcastle-upon-Tyne. The real pleasure of Red Monkey is how their joie de vivre comes out on the low end: they pulse, feint, and groove, usually not in 4/4 time, as they sing about the political world as if they were staring into each other’s eyes.

Erase Errata’s Other Animals, on the other hand, actually is a debut LP, and an impressive one: prickly, trebly calculated dissonance from a San Francisco quartet with a reputation for frenetic 15-minute sets. Music this chaotic doesn’t often use empty space this effectively, but every gnarled note they play is a new attack. Drummer Bianca (like Red Monkey, they’re not big on last names) forces the beat forward like disco’s nasty little cousin while the rest of the band stagger off in separate directions with improbably perfect choreography. The album’s cover shows two mechanical insects having a boxing match, an idea that fits the album nicely: cool, alien, and over too fast to make sense of without a replay.