Named for the late jazz pianist/composer Loonis McGlohon, a gracious artist who urged me to write for nationwide jazz publications, McGlohon Theater has always been a wonderfully atmospheric theater and concert venue, especially around Christmastime when its stained-glass windows add to the magic. But nestling into our aisle seats in Row J, not as far back at the McGlohon as you might presume, I have to admit it was a little intimidating to be sitting face-to-face with a 16-piece big band – four trumpets, three trombones, five saxophones, and a four-man rhythm section, including a guitarist and bassist/bandleader John Brown – with high-powered vocalist Nnenna Freelon yet to come. But the surprisingly intimate 700-seat hall accommodated the stageful of musicians perfectly, neither swallowing the sound nor blasting it.

Though nothing in the John Brown Big Band publicity suggested that this concert, the second in a Swing Jazz Series quartet stretching into next April, was to be a Christmas concert, Brown and his jazz machine boisterously hinted at it from the first downbeat, launching into a brassy rendition of “Rockin’ Around the Christmas Tree.” The reason for all the Yuletide cheer became clear soon enough, as Brown directed our attention to the Spirit Square lobby outside, where Freelon’s newest CD was on sale, simply titled Christmas, backed by the Brown Big Band and not quite a month old. I’ll confess that I became somewhat impatient for the Grammy-Award-nominated vocalist’s arrival. “Let It Snow” swung reliably enough, with a creditable solo from Brown, but guitarist Kevin van Sant was insufficiently amped for his solo to be heard, a problem that would plague soloists later on as well. “I’ll Be Home for Christmas” only served to expose the trumpets as the weak sector of the orchestra, and “White Christmas,” featuring Shaena Ryan on baritone, didn’t showcase the crème de la crème of the reed section.

Fortunately, there was some heavy instrumental artillery in reserve to back up Freelon. She made a welcome splash with a Frank Foster arrangement, “Swingle Jingle Bells,” turning the familiar “dashing through the snow” bridge into a frisky waltz. Then came a lovely detour into Ellingtonia, “I Like the Sunrise,” from the Duke’s Liberia Suite. While dragging “Jingle Bells” into the jazz idiom was comparatively simple, with a flatted note or two along the way, Freelon parked us at intermission by taking us on a similar voyage with “Little Drummer Boy,” a more impressive feat. Adding to the savory aftertaste was a fine alto sax solo by Will Campbell, easily the best so far. The Big Band was cheerier after the break as Brown and his rhythm section started off with a mash-up of “Rudolph the Red-Nosed Reindeer” and “Jingle Bells,” while the remaining members of the band were deployed to the far wings of the house. Brown escalated his previous invitation to the audience to get up and dance into a positive insistence, though not quite with the childish pugnacity of a Republican congressman. Evidence of people moving their “thangs” could be espied at various intervals in the orchestra and up in the balcony, so Brown did not have to carry out his threat of not playing another note.

There was more righteous swinging here than the Big Band had been able to summon up previously, but what should have been a huge highlight, the “Peanut Brittle Brigade” from Ellington’s arrangement of The Nutcracker Suite, fizzled when it might have sparkled as the clarinet and tenor sax solos were under-mic’d to the point of virtual inaudibility. Thankfully, that was the last blemish on the evening as Freelon returned to the stage while the rhythm section struck up the familiar vamp from Miles Davis’s “All Blues” – only Freelon steered it into a cool modal version of “Silent Night,” abetted by a fine solo from her pianist, Brandon McCune. Yet another tasty track from the new Christmas compilation followed, a cuddly vocal duet with Brown on “Baby, It’s Cold Outside,” spiced with a second sampling of Campbell’s fine alto. The hits kept coming with a “Spiritual Medley” that included “Children Go Where I Send Thee,” “Go Tell It On The Mountain,” and a pupu platter of “O Little Town Of Bethlehem,” “Joy To The World,” and “Angels We Have Heard On High.” Interplay between Freelon and trombonist Mitch Butler, a well-kept secret until this point, steered the gospel meeting of tunes to a final jazzy destination. After such bravura, the audience predictably demanded an encore. Freelon and the band ended the concert the same way they end their new CD, with a full-blown version of “I’ll Be Home for Christmas” that gave us Brown and McCune at their virtuosic best. Unlike the purely instrumental version earlier in the evening – and definitely unlike what you’d expect – “home” sounded very much like New Orleans, allowing the band members with portable instruments to parade off the stage and through the audience with a Mardi Gras flair. Nor was it a shabby advertisement for the product available in the lobby.