Jewlia Eisenberg is a straight-up nerd and proud of it. The heart of her recent Trilectic (Tzadik) is the kickiest a cappella song cycle ever written about early-20th-century radical Marxist philosophers. It had its origin on, of course, a bookshelf. "I was browsing through a friend’s library," she recalls, as usual talking a mile a minute. " ‘Dervishes in Turkey? Not that interesting. Early Christian martyrs? No. Maybe mediæval Spanish Jewish poetry? No.’ Then I ran across Walter Benjamin’s Moscow Diary. The first time I read it, I was in tears, it’s so beautiful. The second time I read it, I was laughing. This guy was such a fucking nebbish. He goes to Moscow to meet this woman Asja Lacis; she’s just had a nervous breakdown, her kid is sick, and she’s having two other affairs. One of them is this guy Bernhard Reich, who’s been selected to be Benjamin’s translator. And this other little babe is trying to hook up with Benjamin all the time. He writes, like, ‘One time I was hanging out with Asja, and she said she hoped that the next time I saw her I was fit enough to be at her every day. . . . I said, I will never be that until we resolve the other difficulties in this relationship. And afterwards I couldn’t get to sleep.’ After that I was like, ‘I’m setting this motherfucker.’ "

For her "Trilectic Suite," an examination of the relationship between Benjamin and Lacis, Eisenberg arranged excerpts from the Moscow Diary and Lacis’s autobiography, in both English and German, as well as a few imagined interior monologues. They’re performed by her outfit Charming Hostess in its incarnation as an a cappella trio (with Carla Kihlstedt and Nina Rolle). Eisenberg commands pretty much every extant vocal technique, and she combines them at will — not just traditional styles of harmony, but vocalized breathing techniques, mouth percussion, you name it.

"At the end," she says, "I realized I’d pulled the musical ideas from two main areas. One was Jewish-derived sources: mediæval Andalusian stuff, klezmer, and Eastern European forms. The other chunk was entirely drawn from African-derived music, from Pygmy hocketing to the forms that hit America: gospel, doo-wop, work songs, prison songs. I’ve always been interested in the way the two diasporas fall together."

If at this point you’re expecting Trilectic to be a dry, solemn piece of scholarship and ethnomusicology, that’s understandable — but you’re wrong. It’s speedy, catchy as heck, and frequently hilarious. "Eskimo Suit" is a deliriously funny bit of high-tension doo-wop that shows off Eisenberg’s knack for contrasting vocal timbres and techniques; "Meister of Kultur," a rant in which Lacis tries to hector Benjamin into joining the Communist Party, becomes a rapid-fire patter song that recalls both Värttinä’s chattering Finnish folk tunes and Harry Partch’s work with the natural rhythms of speech. In performance, Charming Hostess are even more entertaining. The women sing in matching outfits (red, of course — "I grew up with all these Stalinists," Eisenberg laughs), liven up the songs with human beat-boxing and theatrical touches, and wander through the crowd for the occasional traditional gospel tune. (Another Charming Hostess album is due later this year on ReR.)

The remainder of Trilectic’s 19 tracks display even greater range. There are four traditional songs including the Jewish hymn "Adir Hu"; there’s a slow rock song of sorts (with bass and drums) called "Sicily" and three of what Eisenberg calls "short-lived love songs": wry miniatures about impossibly screwed-up desire. One of them, accompanied by harmonized snickers, goes, "I can be here in your bed. I can go to a café. But I can’t be in your bed and go to a café — that’s too serious."

For a record about politics and sex and sexual politics, Trilectic maintains a careful distance from its characters’ political stance. The relationship between Lacis and Benjamin was inextricably linked with the idea of revolutionary art and work in the service of the Communist state. As Eisenberg puts it, "they couldn’t be in bed without talking." The biographical remoteness and the witty vignettes of Trilectic frame it as a portrait of a time when the passion for argument seemed much more meaningful. "I named the album," Eisenberg says, "in part because there are three singers and three characters, but also as a joke. It’s not a dialectic response — we’re past that!"