BY JUD COST

If you missed the heyday of those full-throttle progressive German bands collectively referred to as Krautrock (Can, Amon Duul II, Kraftwerk, Ash Ra Tempel, Tangerine Dream and others), Tortoise is your best (and maybe last) chance to get a feel for what was going down in the late '60s/early '70s. Some of this sound spilled over into the British prog rock scene (Caravan, Van der Graaf Generator, Soft Machine), but it was the Germans who really nailed it.

Excited critics may have labeled their early releases "post-rock," but to those who'd been around a while, Tortoise's Teutonic roots were definitely showing. Of course, the Krautrock scene was never an army of robots goose-stepping down the autobahn, and Tortoise added a few distinct ingredients of its own to the mix, including the sweeping, minor-key soundtrack moves of Ennio Morricone and David Lynch maestro Angelo Badalamenti, as well as a low bow in the direction of revolutionary free jazz vibraphonist Bobby Hutcherson.

It all began for the ancient shelled reptiles from Chicago in 1996 with their beautifully understated debut album Millions Now Living Will Never Die , a real breath of fresh air from founding Tortoise members Dan Bitney, John Herndon, Douglas McCombs, John McEntire and David Pajo. By the time they'd released the equally brilliant  TNT  in 1998, they'd added guitarist Jeff Parker as a replacement for Pajo (the former guitarist with Slint).

That same lineup has lured a houseful of rabid fans into San Francisco's Great American Music Hall tonight for a rare glimpse of their heroes-whose new work, Beacons Of Ancestorship (Thrill Jockey) is their first album in five years-in full flight. It's a thrill to watch these craftsmen at work in front of a 15 by 12 foot movie screen which takes the place of normal stage lighting. As film of a sprawling midwest landscape, followed by a rogue's gallery of black and white faces and birds in flight, flickers behind them, Tortoise wastes no time shifting into high gear.

The basic instrumentation of the quintet-a couple of vintage, multi-tasking keyboards, vibes, guitar, bass and drums-is made larger by band members constantly changing instruments like a backwoods fire drill. At Tortoise's most heated moments, you get the feeling this is what it must have been like in 1966 at London's most celebrated underground rock club, UFO, the place that nurtured the early days of Pink Floyd. Or maybe even the rolling thunder of the scuffling days of Sun Ra's Intergalactic Arkestra.

The vivid images projected behind the band blur the lines between reality and cinema to the point that you feel you've just awakened from an all-night LSD bender to find yourself flat on your back, underneath a menacing network of children's monkey bars. At times tonight, l flashed back to an evening long ago when exotic smokeables extended a journey across the Bay Area's San Mateo Bridge (admittedly a long one at over eight miles) to what seemed like an hour, at least.

If you sometimes get the feeling you've seen it all, you owe it to yourself to spend an evening with Tortoise. Their expansive music will suck you into their universe with the inevitability of someone stuck hip-deep in quicksand.

[Photo Credit: Jim Newberry]