One ordinarily goes to a concert with certain expectations. It’s always satisfying when they’re met, but even more so when they’re exceeded in surprising ways. I had high hopes for both Tuesday’s and Wednesday’s concerts in the concluding week of this year’s Jazz in July series at the 92nd Street Y. But shows supplied plenty of unexpected thrills.

I have reached the point where I approach a new appearance by James Moody — the legendary saxophone master and irrepressible funster — the same way I look forward to a rerun of “The Simpsons”: Even if I have heard all his jokes and comedy bits a million times by now, somehow that doesn’t make them any less funny.

Mr. Moody is so entertaining that he could easily fill a whole set with just vocals and shtick, but what a loss to jazz that would be, since the diminutive 82-year-old giant (who’s barely taller than his horn) is playing better than ever. Concentraing on tenor these days (he used to triple on alto and flute), his tone is rich and supple, and his improvisations never fail to enthrall.

Arts organizations all over the world are practically falling over themselves to present Mr. Moody in concert — Jazz at Lincoln Center has done so several times, most recently in January — and with good reason: He is one of the few survivors of the early bebop era still playing at peak level. When he’s not knocking you out with his playing, he’s splitting your sides with one-liners. On Tuesday night, Mr. Moody was pushed to further heights by his fellow frontliners — trumpeter Jon Faddis and clarinetist Paquito D’Rivera — who were well-chosen to help him with both the music and the comedy. Normally, either one of them is the class clown, but Mr. Moody turns them both into deadpan straight men.

Other than Mr. Moody’s routines, the evening’s repertoire consisted of jazz classics and the occasional standard: Charlie Parker’s blues “Au Private,” Dizzy Gillespie’s Cubanesque “Con Alma” (introduced by Mr. Moody and bassist Todd Coolman in Slim Gailliard-style mock-Spanglish), and a marvelous tenor feature for Mr. Moody and Jazz in July artistic director-pianist Bill Charlap on “Body and Soul.” The show concluded with Gillespie’s scat-centric “Oop-Pop-A-Da,” but I was more impressed with the first act closer, “Eternal Triangle,” the late Sonny Stitt’s contribution to the “I Got Rhythm” variation stakes.

The musical highlight, however, was neither a standard nor a shtick, but the only Moody original of the night, “Last Train From Overbrook.” It’s a marvelous, train-like melody, expertly played by the full septet, on which the youngest member of the frontline, the alto saxophonist Antonio Hart, contributed his most solid solo of the evening. Which brings to mind another point: With Mr. Moody doing so many concerts for so many ambitious organizations, why do they only keep sponsoring in him in basic jam sessions? Throughout the 1950s, Mr. Moody led a firstrate octet, for which he composed and arranged a series of classic albums, most famously the 1958 “Overbrook.” No one has ever revived this music, and it would make perfect sense for someone to do for Mr. Moody’s compositions what the 92nd Street Y did for Phil Woods last week by presenting him with a little big band — and rehearsal time.

One of the bigger surprises of Tuesday night’s Moody-fest was a piano feature for Mr. Charlap and Mr. Moody’s regular pianist, Renee Rosnes: Before Mr. Moody did his classic “Moody’s Mood” routine, Mr. Charlap and Ms. Rosnes introduced it with their own four-handed variation on Jimmy McHugh’s “I’m in the Mood for Love.”

That set the scene for Wednesday’s “Piano Jam.” Here, the center stage was occupied by four formidable keyboardists: two prodigies (the 40-year-old Mr. Charlap and the 37-year-old Eric Reed) and two 80-something veterans (Barbara Carroll and Dr. Billy Taylor). I could have left after the first five minutes and been thoroughly satisfied. I’ve been waiting for years to hear Messrs. Charlap and Reed engage in a two-piano challenge, and the show began with the two of them diving into Benny Golson’s “Stablemates” on enormous grand concert Steinways, dispensing gun-slinging improvisations at lightning speed. Trying to breathe along with them and follow every note could be fatal — children and piano students, don’t try this at home.

As with every piano jam, an annual feature of the Jazz in July series, the bulk of the evening was fashioned around the pianists, in both solos and multi-Steinway duets. As individual features, both venerated masters chose Billy Strayhorn, with Ms. Carroll rendering “Something To Live For” with her trademark translucence, and Dr. Taylor fashioning an interesting but ploddingly slow “Take the A-Train.” (If the actual A-train went this slow, we wouldn’t get to Harlem for a long time.) Representing the Junior Circuit, Messrs. Charlap and Reed responded with a four-handed Duke Ellington segment that seemed like a direct extension of the Maestro’s own extended, unaccompanied piano medleys.

Yet it was two non-pianists who stole the show: the vocalist Ethel Ennis and the tenor saxist Harry Allen. Ms. Ennis, who will turn 75 in November, recorded six excellent albums between 1955 and 1964, toured with Benny Goodman, and then pretty much disappeared to her native Baltimore. Heard today, she sounds like a Shirley Horn disciple (especially on the duet on “But Beautiful” with Mr. Charlap), but since Ms. Ennis was recording much earlier, it may well be the other way around. She is swinging and playful yet respectful enough of the songs to get the intended point across with a light, understated voice and solid time.

Ms. Ennis opened with more Ellington, “Love You Madly,” and built to “Empty Bed Blues,” which romped much more joyously than Bessie Smith’s slow and sultry 1928 original. Mr. Allen also took top honors in front of Messrs. Taylor and Reed in a jam that began with Sigmund Romberg’s “Lover, Come Back to Me” and ended with Coleman Hawkins’s bebop variation, “Bean and the Boys.” An unstoppable butt-kicker, Mr. Allen’s finest moment was Thad Jones’s touching “A Child Is Born,” which he performed as a duo with Ms. Carroll. It was the loveliest ballad I have ever heard from him, overflowing with paternal tenderness.

The “Piano Jam” climaxed with yet more Ellingtonia — “Caravan,” an exciting if predictable feature for the drummer Eddie Locke — and with the entire company, including Ms. Ennis and all four pianists, on “Honeysuckle Rose,” which included snippets of “Maple Leaf Rag” and “Ebony Rhapsody.” It was rushed and crowded, but even that gave me the chance to quote one of Mr. Moody’s newer jokes.

“Why did God invent time?” the mercurial saxist asked on Tuesday night. “Because without it, everything would happen at once.”

wfriedwald@nysun.com