By Chris Tweney

MARCH 23, 1998:  In early 1994 a hodge-podge assortment of underground bands who didn't, uh, rock in the traditional sense began to surface, among them Chicago's Tortoise and their Thrill Jockey labelmates Trans Am. The aesthetic these bands embraced was closer to the meandering, hallucinatory impetus of dub than anything else. British critic-at-large Simon Reynolds quickly dubbed the emerging subgenre "post-rock," thereby unifying a disparate array of groups, including Stereolab, Pram, Main, and Seefeel, under an umbrella so general it left many wondering, "What is it, really?" But what these groups shared in a loose sense was that they all played "older brother" music -- the sort of thing your hip, slightly geeky big brother (who need not be genetically related) might introduce you to in order to widen your musical horizons.

In post-rock, the traditional trappings of rock are often hijacked and subverted; guitar heroes, lyrics, the three-minute song, even Top 40 ambition are all notably absent. (For example, neither Trans Am nor Tortoise have a vocalist.) That approach can be traced back at least as far as Slint's 1991 album Spiderland (Touch and Go). But the roots go even deeper, into late-'60s prog-psychedelic sources, including Pink Floyd, Can, Brian Eno, and Kraftwerk. There's also a strong post-punk and no-wave influence. You might say that post-rock is what happens when the pretensions of prog get a good thrashing by punk noise. All these elements are present in Tortoise's TNT and Trans Am's The Surveillance (both on Thrill Jockey), two of the latest reports from the post-rock front.

Trans Am may be one of post-rock's lesser lights, but they've gotten extensive coaching and production help from John McEntire, the electronics wizard and drummer behind Tortoise. The Surveillance takes the "big-brother music" theme into some hard-rocking territory, delivering a sustained barrage of ferocious guitar riffs mixed with breaks of rhythmic electronic noise (static, telephone busy signals, looped feedback). The band have roots in riff-heavy metal, but their sense of rhythm is tied to high-end digital-sampling technology. Picture a video-game-obsessed teenage metalhead given a good course in nonlinear sound editing (the use of computers to chop, sequence, and tweak every last note) and you get an idea of the joy Trans Am take in the sounds of machines being tortured.

If Trans Am's starting point is the power-chord riff, then Tortoise's alpha and omega is the ambiance of a noodling, heavily EQed bass line. Put two bass players, three drummers, and a guitarist in a room with analog synths, electric piano, and a really serious digital editor and they're going be, well, noodly. Tortoise's sound is contorted, sinuous, almost obsessive -- they seem to write songs by inventing a musical crystal that repeats itself methodically in 12 different ways before disappearing, only to return later when you're least expecting it.

That technique was perfected on their last full-length, Millions Now Living Will Never Die, and it returns in force on TNT. Indeed, the new disc is nothing if not cinematic. "The Equator" dissolves a twangy, Ennio Morricone-style guitar lick into a sauntering, horse-gaited groove; "A Simple Way To Go Faster Than Light That Does Not Work" explodes into driving, funky meta-dance music; and "Four-Day Interval" echoes the Western motif of "Equator" on a head-nodding tour of Tortoise's musical galaxy. TNT is also markedly more lush than their previous work; where Millions was almost too full of near-silent, brooding moments, the new CD crams almost every nook and cranny full of intricate, multi-layered sound.

On the technical side, TNT marks the first time Tortoise have made extensive us of nonlinear sound editing, and it shows: some of the tracks, particularly the final suite, dive into strange waters that come close to the weirdstep drum 'n' bass of Plug. But the biggest difference is one of speed: this time the group spend much less time in the plodding, methodical mode that led critic Robert Christgau to dub them, unfairly, "the deadly Tortoise." That view may be rooted in the suspicion that post-rock is merely rehashing the self-indulgent wankery of the prog era. But there's a rewarding method to the mad eclecticism and convoluted structures of TNT and The Surveillance, one that channels the anxieties of our postmodern digital age into a surprisingly delicate, emotionally charged lyricism. And it's got nothing to do with misplaced nostalgia for the days when virtuoso guitar gods ruled the realm of prog.

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