IN the liner notes to the 1966 album "Freak Out!" by the Mothers of Invention, you can find the following things: annotations on the 14 songs, describing them variously as "very greasy," "trivial nonsense" and "what freaks sound like when you turn them loose in a recording studio"; an advertisement for a map that promises to reveal the "Freak-Out Hot Spots" of Los Angeles; and a hat-tipping list of 180 influences, musical and otherwise, that includes Slim Harpo, James Joyce and Charles Ives.
You can also find a boxed credit, standing apart and alone, that says, "All selections arranged, orchestrated and conducted by Frank Zappa."
The confidence in that credit along with a photo of the composer himself in sunglasses wielding an upside-down drumstick like a conductor's baton signaled the self-possession that would guide Zappa, then just 25, through the 60-plus albums of his singular career.
Forty years on from that debut, a band led by Zappa's son Dweezil and featuring several of his former associates is seeking to illuminate the rigorous ambition and musical iconoclasm of his work. The Zappa Plays Zappa tour, which arrives at the Beacon Theater in New York on Monday after an extensive European leg, is the first memorial effort by his family since Zappa died of cancer in 1993.
"My overall goal in doing this is to present Frank's music to a newer audience," Dweezil Zappa, 36, said in a phone interview from the Los Angeles area last month, the day before heading out for the tour. "I think his music for one reason or another kind of skipped some generations that didn't get a chance to discover it."
He has recruited a roster of guests that includes the guitarist Steve Vai, the drummer Terry Bozzio and the singer-saxophonist Napoleon Murphy Brock, all of whom recorded and toured with his father in the 1970's and 80's. The tour has been a long time in the making. "It took me close to two years to get some of the stuff I wanted to get together," Mr. Zappa said.
Mr. Brock, speaking by telephone from Manchester, England, two weeks into the tour, said he remembered first meeting Dweezil as a small boy. "It's quite phenomenal that I would be able to be here with the son as I was here with the father," said Mr. Brock, whom Zappa discovered in 1972 fronting a dance band in Hawaii. "We're representing the authenticity of these songs."
As a cultural figure, Frank Zappa is in the odd position of being both relatively well known and artistically obscure. His name and face with its trademark handlebar mustache and goatee remain familiar to millions of people who would be hard pressed to name many songs beyond novelty hits like "Valley Girl" (which featured Dweezil's sister Moon Unit) and "Don't Eat the Yellow Snow."
That is what Dweezil Zappa and his mother, Gail, hope to remedy with a tour that they envision as an annual event. "Hopefully people will understand that this music is alive and well," Gail Zappa said by phone, "and it's going to be around for a long, long time."
Even in the freewheeling era that formed him, Zappa was an odd man out an abstemious aesthete who turned his withering satire on the counterculture as readily as he attacked the deadening conformity of public schools, government and social institutions in general. His lyrics could be absurdist or tender, scatological or philosophical, and they were joined to knotty melodies full of hairpin time changes and subject to gleeful mixing-board manipulation. He was also a political activist of a determinedly centrist stripe, calling himself a moderate Democrat and a conservative, arguing passionately for freedom of speech (most famously in Senate hearings on obscenity in music in 1985) and exhorting his fans to vote.
The set list for the tour includes some of his most adventurous and challenging pieces, like "Inca Roads" and the notoriously difficult "Black Page," which Zappa originally wrote as a drum solo for Mr. Bozzio (the name comes from the density of notes that covered the sheet music). Dweezil Zappa said he was especially drawn to the albums he remembers from his childhood in Southern California, from the era after his father dissolved the Mothers of Invention.
"He was blending rock and jazz and classical in the middle 70's in a way that nobody else was," he said.
Although the tour is at least touching on Zappa's earlier work songs like "Hungry Freaks, Daddy" (the first track on "Freak Out!") and "Let's Make the Water Turn Black" from "We're Only in It for the Money," Zappa's sardonic response to "Sgt. Pepper's Lonely Hearts Club Band" it is heavily weighted toward the middle of his career, the period that defines Zappa for many of his fans. (There is no "Valley Girl," but casual fans will at least be able to find "Yellow Snow" and "Montana" in the mix.) Response to the European shows in online forums has been largely positive. On the Zappa-centric blog Kill Ugly Radio, one fan wrote of the May 19 show in Stockholm: "This was my first chance to experience the music of FZ live in concert. And what a concert. Sitting there on the fourth row from the stage, I found myself with BIG smile on my face, laughing out loud at times."
Gail Zappa said feedback on the family's Web site (zappa.com) had been similarly warm. "It's all age ranges," she said. "The older guys say, 'Oh, I saw Frank seven times, and now I'm taking my 14-year-old son who's a musician,' or 'my 7-year-old daughter who loves 'Freak Out!' "
Zappa's own children Moon, Dweezil, their younger brother Ahmet and their younger sister Diva were involved with their father's music in various ways from young ages. (Given Zappa's relentless recording and touring, it may have been the only way to bond with him; Moon has said she suggested the idea for "Valley Girl" via a note slipped under the door of his recording studio.) All four shared writing or performing credits on Zappa songs from the 70's and 80's. Frank also produced Dweezil's first album, "Havin' a Bad Day," in 1986, and released it on his Barking Pumpkin label.
The Zappa siblings have gone on to an assortment of show business projects. Dweezil has recorded another half-dozen albums, sometimes with Ahmet providing vocals, and has been host of shows on MTV and the Food Network. Ahmet, who married the actress Selma Blair in 2004, is currently working on a book, his mother said. Moon has acted on television and in films. Diva has also had small television and movie roles, and released a single with Dweezil in 1999 that featured Tipper Gore on drums. (Ms. Gore, wife of the former vice president, was a target of Zappa's ire during her decency campaigns in the 80's. But she subsequently became a friend of Gail Zappa, who supported Al Gore for president in 2000.)
But Frank Zappa's work has remained central to the family. Both Dweezil and his mother come across as fiercely custodial of that legacy, fighting against copyright infringements and advocating for the music to be played as it was written. "My job essentially is to protect the intent of the composer and the integrity of the work," said Gail Zappa, 61, who had been married to Frank for 26 years when he died.
Dweezil Zappa said that despite his years of experience on the guitar he started learning when he was 12 playing and arranging his father's music was a significant challenge. For one section of "The Black Page," he had to "completely change my technical style of picking to accommodate what was needed to play this accurately."
"That was probably a two- or three-month process of intensive playing and studying," he said.
Zappa's stature among a cult of musicians and scholars has continued to grow since his death. His works have been recorded by companies including the German chamber orchestra Ensemble Modern and the French woodwind quintet Le Concert Impromptu. Last fall, the Oregon Percussion Ensemble presented a double bill of pieces by Zappa and one of his idols, the French composer Edgard Varθse. He is especially well regarded in Europe: the former Czech leader Vaclav Havel has long proclaimed him an influence and a group of artists in Vilnius, Lithuania, erected a statue in his honor in 1995.
Andy Hollinden, a lecturer who teaches a course on Zappa at the Jacobs School of Music at Indiana University, called him "my favorite writer of melodies ever." Zappa, he said in a phone interview, "is different from everybody else in my opinion, in that he was a composer who wrote for electronic instruments in the rock 'n' roll era."
Zappa has attracted other disciples tribute bands like Project/Object in New Jersey and Bogus Pomp in Florida somewhat to his family's dismay.
"People get upset with me sometimes when I say I've never heard Frank's music played correctly," Dweezil Zappa said. "If there were people out there playing it correctly, with the right spirit, with the right notes, I'd be the first one to get excited."
But Ed Palermo, a New York saxophonist who has been performing big-band arrangements of Zappa's music since 1994 (most recently at the Iridium in Manhattan), said Zappa was subject to inevitable recontextualization.
"I believe Zappa deserves to be known down through history as a musician of the caliber of Gershwin and Duke Ellington," said Mr. Palermo, who has just released an album of his Zappa arrangements called "Take Your Clothes Off When You Dance."
"I know the Zappas are very protective, and it's admirable," he continued. "But I think they're looking at it from a classical point of view. I do what jazz musicians do, in reinterpreting the music."
Gail Zappa is not completely dismissive of anyone's efforts to burrow into her husband's work. "I think that people should attempt it, and somebody will get it right someday," she said. "But because they're not operating under the baton of Frank, or even Dweezil, you can only take it so far."
Mr. Brock, the singer and saxophonist, said that the only thing missing from the tour was the restless, irrepressible presence of Zappa himself.
"I think Frank would be smiling and dancing and playing and laughing," he said. "And making up some new lines for us to play."