The cover of Tony Bennett’s new album, “Tony Bennett Duets: An American Classic,” utilizes a clever conceit that Mr. Bennett, a lifelong student of the visual arts, must surely appreciate: his face, constructed pointillistically out of a zillion tiny little buttons bearing pictures of him from the 1940s all the way to the millennium. The message is clear: Mr. Bennett, who is celebrating the release of the album as well as his 80th birthday with an all-star concert tonight at the Theater at Madison Square Garden, is a product of his past identities — the pop crooner of the early ’50s who gradually reinvented himself as a major jazz stylist in the ’60s and ’70s before going on to become the savior of the Great American Songbook in the ’90s.

In 1993, Mr. Bennett participated in “Frank Sinatra Duets,” the album that launched the mega-star duets trend. Upon the release of that album (as well as the subsequent “Duets II”), many long-time Sinatra fans felt that the Chairman of the Board had been inveigled into participating in a coarse enterprise designed to sell a lot of records and get his name on the charts.

Indeed, most of the tracks on Sinatra’s duets packages were sadly forgettable. Thankfully, on Mr. Bennett’s “Duets,” the ratio is reversed; there’s nothing as embarrassing as Julio Iglesias stumbling through “Summer Wind,”looking not only for lost love but the beat.

The difference between the two projects is that Sinatra simply laid down his tracks and left it to producer Phil Ramone to do everything else. The original Sinatra vocals, as a subsequent bootleg revealed, actually sounded much better bereft of the electronic additives. Contrastingly, Mr. Bennett’s effort is not what the late New YorkTimes critic Hans Fantel called “sonic collage,” but true duets, with two people actually relating to each other live in the studio. There are moments that appear, at least, to be genuinely spontaneous, as in “For Once in My Life,” when Stevie Wonder interjects a quote from “I Left My Heart in San Francisco” into his harmonica solo, provoking a laugh from Mr. Bennett.

The Sinatra duets albums also featured a number of flavor-of-the minute performers whose careers were virtually over by the time the albums were released. Contrastingly, although most of the stars on “Tony Bennett Duets” are not necessarily versed in singing the Songbook, nearly all are established icons whose careers have already transcended the usual obsolescence of the pop music business, like Sting, Bono, Paul McCartney, and Elton John. It is also an indicator of how much music has improved over the last dozen years that two of Mr. Bennett’s younger costars, the Canadians Diana Krall and Michael Buble, both specialize in jazz and the Songbook.

Even before we consider how well the co-stars handle their appointed tasks, it should be noted that the production values on the current album are terrific. Mr. Bennett’s musical director and pianist Lee Musiker, string orchestrator Jorge Calendrelli, and horn arranger Torrie Zito (who has worked with Mr. Bennett for 40 years) have collaborated to rewrite or amend classic Bennett charts by Ralph Sharon, Johnny Mandel, and others in a way that preserves the best of the past.

Mr. Bennett’s own chops are amazing: even at 80, his voice is as big and warm as ever; it’s a sound that ages well and is more capable than ever of conveying the microscopic nuances of both sadness and elation. In playing his current vocals side by side with those as far back as 55 years ago (on “Boulevard of Broken Dreams,” his first single) the new performances do not suffer. More than ever, Mr. Bennett’s voice sounds like going home.

The most difficult problem for singers not versed in jazz is trying to sing with a swingtime feeling; Mr. Bennett, Mr. Musiker, and the arrangers confront this problem intelligently, giving two of the faster tunes, “The Best Is Yet To Come” and “Just in Time,” to Ms. Krall and Mr. Buble, who know well where the beat is. The Dixie Chicks have a rougher time of it on “Lullaby of Broadway,” a hard swinging Sharon chart introduced by Mr. Bennett and Count Basie, but work around it intelligently, coming up with a simpatico impression of the Andrews Sisters.

On “Smile,” Mr. Bennett sings with so much heart and soul that he reaches a Louis Armstrong level of radiance, so much so that even Barbra Streisand, who usually seems incapable of expressing love for anyone other than herself, gets the point. (That said, having Celine Dion on the same album as Ms. Streisand, on “If I Ruled the World,” seems redundant.) The tunes and charts generally play to the strengths of the guest stars: Sting sings “Boulevard of Broken Dreams” as if it was one of Kurt Weill and Bertolt Brecht’s decadent tangos; Elvis Costello brings his sense of humor to “Are You Havin’ Any Fun”; and “Because of You” showcases K.D. Lang’s considerable capacity for dreamy rubato ballads.

Still, the duet format has its limits: When Mr. Bennett crosses cadenzas with George Michael on “How Do You Keep the Music Playing,” the Greek-British pop star doesn’t even try to keep up with the grandfatherly icon on the chart’s famous climax, in which Mr. Bennett executes a breathtaking chromatic ascent to a mountainous high note.

Mr. Bennett obviously realized no other voice could possibly add anything to his signature song, “I Left My Heart in San Francisco,” nor could any other instrument, and therefore sings it with just Mr. Musiker on piano.This is apparently the only studio version of the song that he has cut since the original in 1962, and he leaves us no doubt that his heart is still waiting for him, high on that bay city hill, even after 45 years. Make no mistake, Tony Bennett more than knows how to keep the music playing.