Elling tells us at the outset that he’s feeling mellow; they worked hard the first set and want to take it easy—for a while at least. He opens by reading Kenneth Rexroth’s poem “Lute Music”). Rexroth once noted, “I write poetry to seduce women and to overthrow the Capitalist system.” This is a poem of seduction: “Here at the year’s end…let us bring to each other…the precious metal of our mingled hair, the frankincense of enraptured arms and legs….” The poem and trio accompaniment segue into “Stairway to the Stars,” the 1939 lyric by Mitchell Parrish that has been recorded hundreds of times (by Kevin Mahogany, Chet Baker, Johnny Mathis, Ella Fitzgerald, and others) but so far not by Elling. He’s due to release a new album; are we getting a sneak preview?

When you hear Elling live, you’re aware (far more than when listening to his recordings) of how rich and resonant his voice is—like a cello, or a double bass being bowed. It’s almost as if the air around you vibrates. During the beautiful “Stairway,” he gives us low notes and high, leaping from one to the other and always making a perfect landing. He follows with “Detour Ahead” from Flirting with Twilight (2001), throwing in more falsetto in case we’d missed it the first time. Afterward comes some back-and-forth with his band, some shuffling of pages, and Elling’s announcement that “clearly this is a new arrangement for us; we’ll see what happens.” What happens is a terrific version of “Undun,” the late 1960s hit by the Guess Who (“She’s come undone/She didn’t know what she was headed for/And when I found what she was headed for/It was too late”). At the bar, during Laurence Hobgood’s solo, a man plays piano on his own trousers.

The mellow mood has passed by the next song: a ferocious scat number with no lyrics and a tune Elling hears only in his head. Willie Jones III, last seen at the Dakota with Roy Hargrove’s quintet and backing Roberta Gambarini, blazes on the drums. Next up: “Night Town,” a tune by Don Grolnick, former musical director for James Taylor, with lyrics by Elling. (To see some of Elling’s literate, complex lyrics—in English and in French—visit his Web site and click on “The Words.”) Afterward, he reads Duke Ellington’s portrait of the evening hours from Duke’s memoir, Music Is My Mistress: “Night life is cut out of a very luxurious, royal-blue bolt of velvet.” Jazz show or poetry jam? A bit of both.

During Rob Amster’s solo, a baby cries. Eyebrows shoot up as people wonder who would dare to bring an infant to the late set at Birdland. The answer: Elling and his wife. They have a 12-week-old daughter, and Elling is radiant. “The baby doesn’t like the bass,” he jokes, “but she does like the drums.” His next-to-last song is for her: “When Did You Leave Heaven?” Singing, he exudes pure joy. Afterward , he tells the crowd, ”She’ll hear this song when she’s six…she’ll say ‘Dad!!!’ and won’t that be cool?”

The finale: “Nature Boy.” Elling leaps whole octaves at a single bound. You can hear it on his CD The Messenger (1997), but it won’t be the same—no long delicious solos by the band. In live jazz, as Elling says, it’s “never the same set once.”