Just TRY to stay seated when Beausoleil avec Michael Doucet plays Feb. 18 at The Kate

BeauSoleil avec Michael Doucet will perform Feb. 17 at the Katharine Hepburn Cultural Arts Center in Old Saybrook.

Courtesy of Rick Olivier

OLD SAYBROOK — Can it really be 43 years now that BeauSoleil avec Michael Doucet has been touring the world as one of Cajun music and culture’s foremost ambassadors?

You can go ahead and TRY to stay seated — even in such a relatively formal listening room as the Katharine Hepburn Cultural Arts Center, where BeauSoleil will perform in a five-days-after-Fat-Tuesday Mardi Gras celebration on Feb. 18.

But that’s no guarantee that you’ll be able to do it.

That’s because BeauSoleil, propelled in part by Doucet’s cracklingly fluid fiddle and soulful vocals — as well as the familiarity and intimacy that a bunch of killer musicians forge when they play together for decades — is just about the finest Cajun ensemble on the planet.

Is BeauSoleil really “the best Cajun band in the world,” as Garrison Keillor of “Prairie Home Companion” once proclaimed it?

Maybe. Maybe not.

But without a doubt, they’re right up there — and no band can light up a room or get people moving the way BeauSoleil can.

Showtime is 7 p.m. Tickets are available in advance at thekate.org or 860-510-0453. The Kate is located at 300 Main St.

For those who just can’t get enough Mardi Gras, BeauSoleil also will play Feb. 10 — along with Nathan and the Zydeco Cha Chas and the Knickerbocker All-Stars — at the 26th annual Cajun & Zydeco Mardi Gras Ball. It runs from 6:30 p.m. to midnight at the Rhodes on the Pawtuxet ballroom (60 Rhodes Place, Cranston, Rhode Island).

Tickets are $34, available at rhythmandroots.com/mardi-gras-ball.

Formed in 1975 in Lafayette, Louisiana — pretty much the center of the Cajun world — the current touring version of BeauSoleil also features Doucet’s brother, David Doucet, on guitar, mandolin and vocals; Bill Bennet on bass; Mitch Reed on fiddle and bass; Billy Ware on percussion; and Tommy Alesi on drums.

Michael Doucet also plays mandolin and accordion in addition to fiddle.

The band has at least 21 albums under its collective belt — two of which, 1996’s “L’Amour Ou La Folie (Love Or Folly)” and 2008’s “Live at the 2008 New Orleans Jazz & Heritage Festival,” have won Grammys. It has been nominated for at least 11 Grammys over the years.

While BeauSoleil’s song list, much of which includes French lyrics, includes hundreds of traditional songs, the band has never been afraid to mix it up and could not accurately be described as traditional. It mixes in zydeco, for one thing — the music of Cajun music’s Creole cousins.

BeauSoleil, which has toured frequently and ventured as far out into the world as any Cajun band, also has edged out beyond the constraints of traditional Cajun instrumentation, rhythm and lyrics. Its music incorporates a spicy stew of blues, New Orleans-influenced jazz, Tex-Mex, rock ’n’ roll and other genres.