CAMBRIDGE - Al Kooper is, very possibly above all else, an adventurer, willing to put himself into situations where interesting things are bound to happen, for better or for worse. That's how he managed to stumble blindly into rock 'n' roll history - twice - by playing an instrument he knew nothing about (the iconic organ and French horn parts on "Like a Rolling Stone" and "You Can't Always Get What You Want," respectively), and it's how he approached his show with his rockabilly trio Saturday at Club Passim.
With one or two exceptions (like Lynyrd Skynyrd's "Mississippi Kid," for which - in true Kooper fashion - he had quickly taught himself mandolin because he had decided as the band's producer that the recording needed one), much of the material consisted of the songs that set Kooper wandering in the first place. In between, he regaled the crowd with tales of discovering those songs, told stories about the artists he'd worked with over the years, and shared a few amicably crude jokes.
That easy gregariousness was likely what gave Kooper access to folks like Dylan, the Stones, and the late Bo Diddley (who was honored explicitly with "Who Do You Love" and implicitly with Buddy Holly's "Not Fade Away"), but it was his obvious love for music that made him nearly indispensable. Clad in dark shades and a cow-pattern shirt, he began with the ominous opening chords of Link Wray's "Rumble," with bassist Jesse Williams and drummer Mark Teixeira giving Kooper's compressed, reverbed guitar the room it needed to capture the feel of a night ride.
Kooper paid special attention to what he considered his holy trinity of rockabilly guitar: Cliff Gallup (represented by Gene Vincent's "Be-Bop-A-Lula"), James Burton (Ricky Nelson's "Milk Cow Blues"), and Scotty Moore. Moore got the most coverage with four Elvis songs, including a version of "My Baby Left Me" with a tick-tack percussiveness that took full advantage of Williams's upright bass.
A few songs weren't strictly rockabilly, like the mandolin blues of Robert Johnson's "Come on in My Kitchen," the '60s blues-rock vibe of Procol Harum's "Whiskey Train," and the inexorable clop of Tennessee Ernie Ford's "Sixteen Tons," turned a bit smoky by Kooper's low, affectless delivery. But that didn't matter, nor did it matter that he wasn't much of a singer or that sloppiness occasionally seeped through. This was the stuff that Kooper loves, and it flowed through him like a river.