Despite the example of Wynton Marsalis over the past quartercentury, it’s still rare to find instrumentalists who are nearly as accomplished in classical music as they are in jazz. It’s even harder to find players skilled in classical, jazz, and country music; in fact, I can’t think of a single musician whose career parallels that of the violinist Mark O’Connor.

Mr. O’Connor first gained fame as a country music virtuoso and worked for many years as a Nashville session man. He has spent the last decade exploring (and composing) classical music and, more recently, jazz.This week, appropriately enough, he is appearing at Dizzy’s Club Cola-Cola, the venue Mr. Marsalis helped found.

One of Mr. O’Connor’s earliest gigs, when he was 17, was in the band of the most celebrated of all jazz violinists, Stephane Grappelli, on a 1979 tour that included a concert at Carnegie Hall. Mr. O’Connor accompanied Grappelli on guitar and played violin duets with the legendary French fiddler. As further testimony to the diversity of both violinists, they also recorded a live album with pop-bluegrass mandolinist David Grisman. Mr. O’Connor’s current jazz quartet, Hot Swing, is modeled upon the Quintet of the Hot Club of France, which Grappelli co-led with the equally remarkable Gypsy guitarist Django Reinhardt.

These days, tributes to Reinhardt are staged regularly in New York, but Mr. O’Connor shifts the focus to Grappelli and the rest of the Hot Club of France. Like the famous quintet, Hot Swing consists entirely of string instruments: Apart from Mr. O’Connor, there are two guitarists, Stephane Wrembel (who will be replaced by Matt Munisteri for the weekend shows) and Howard Alden, and bassist John Burr, another veteran of Grappelli’s later groups.

Whereas the Django festivals that are staged biannually at Alice Tully Hall and Birdland tend to feel more like Olympic matches in which one contemporary Django-styled guitarist spars with another, here the emphasis is on collaboration rather than competition. Mr. O’Connor’s foursome reminds us that Grappelli was every bit Reinhardt’s equal; it was Grappelli who was the first to solo or state the melody on nearly all of the quintet’s recordings, and Mr. O’Connor does the same with Hot Swing.

The band began its second set Tuesday night with the Gershwin jazz standard “Fascinating Rhythm” before essaying “Gypsy Fantastic,” an original in the spirit of such traditional Romany fare as “Two Guitars.” Like Mr. O’Connor’s classical compositions, this tune demonstrates his ability to compose in a preset style.

The third tune was the only piece in the set by either Reinhardt or Grappelli, the former’s “Nuages.” Hot Swing played it expertly, but this song has become, unfortunately, Reinhardt’s equivalent of “Take the A Train.” Few of Django’s contemporary followers, Mr. O’Connor included, explore his catalog of compositions at any depth; Mr. O’Connor would be the perfect player to revive some of Reinhardt and Grappelli’s brilliant swing adaptations of Bach as well as Reinhardt’s own classically styled works.

Mr. O’Connor then introduced the fifth member of the group, vocalist Roberta Gambarini. Where the four instrumentalists are Americans working in a European jazz idiom, Ms. Gambarini is an Italian inspired by the canon of great African-American jazz singers, especially Ella Fitzgerald. She is a vocal virtuoso, and nearly everything about her singing is perfect – her intonation, her ear for harmony, her vocal tone, her time. So too is her taste: Although she scats a lot, she never does it to distraction.

Yet, as Ms. Gambarini showed on the swinger “Lover, Come Back to Me” and the ballad “Too Late Now,” she’s almost too perfect. Her lyric interpretation can’t keep pace with her impeccable technique, and, probably partly because English is not her native language, she often seems expressionless and detached from the words she’s singing. She also eschews any obvious device that might bring more character to her singing, such as growls, tonal distortions, or dynamics (she sings everything at the same even volume).

The rest of Mr. O’Connor’s set included a Hot Club-style arrangement of Duke Ellington’s “Don’t Get Around Much Anymore” and “Fiddler Going Home,” an original dedicated to another of the leader’s mentors, the pioneering jazz violinist Claude “Fiddler” Williams. Interestingly, the latter was more of an Appalachian or Celtic dirge than a jazz piece. Both of these pieces and most of the others in the set are included in Mr. O’Connor’s new album, “Mark O’Connor’s Hot Swing Live in New York” (Omac 19).

Throughout, Mr. Wrembel and Mr. Alden switched off guitar roles between rhythm and solo playing. Mr. Wrembel sounded just like Django, whereas Mr. Alden, who was rightfully introduced by the club’s host, Todd Barkan, as a “quiet legend,” played like himself while throwing in a few Reinhardt trademarks. Mr. Burr drove the ensemble with the slapping style prevalent among bassists of the pre-Jimmy Blanton era.

Mr. O’Connor wound up with his musical tongue-twister “Pickles on the Elbow,” a fast and dazzling piece that is half jazz stomp and half bluegrass breakdown. I have never heard its like before and do not expect to again until Mr. O’Connor, who informed the crowd that he has recently become a New York City resident, next takes the stage.

Until January 22 at Dizzy’s Club Coca-Cola (Broadway at 60th Street, fifth floor, 212-258-9595).