The key to making that world last a lifetime is more than just talent, though that undoubtedly helps. You also need persistence, countless hours of practice, consistency and, while this sounds contradictory, an ability to innovate, to move with the times and your own muse. At any rate, that's a pattern that seems to have worked for Spyro Gyra, one of the most successful and longest lived jazz assemblages to come on the scene in the last few decades. As Jay Beckenstein, the saxophonist who pulled the group together in the early 1970s, notes, "This band has always opened up the creative sides of everybody who's in it. We always want to try new things and keep exploring new ideas, and that has kept it fresh."

It's also led at least one critic to identify Spyro Gyra as the Grateful Dead of the contemporary jazz scene -- a group that finds ways to evolve and, most important, stay together regardless of the shifting trends around it. At the same time, over a career that's included 18 albums, it's managed to sell as many records as many pop groups, an unusual accomplishment for a band that's managed to remain true to its jazz origins.

Spyro Gyra evolved from a shifting ensemble of musicians in Buffalo, New York, that was anchored by Becken-stein's saxophone. The group bounced around the club scene until one club owner decided he wanted to hype them, and asked for a name to go on the advertisements. Beckenstein jokingly suggested something he remembered from college biology -- spirogyra, a type of freshwater algae. The club owner misspelled the term, substituting a "y" for the "i," and also misheard it as two words. Still, Beckenstein decided he liked the moniker, and kept it.

The group recorded its first album while doing session work for what were considered more commercial products, but the result was successful enough to attract the attention of a local record label, which signed them to a deal that was soon transferred to Infinity, a division of MCA. Not long after having their contract picked up, Spyro Gyra recorded the platinum-selling Morning Dance, which in 1979 spawned a Top 40 single of the same name.

Since then, Spyro Gyra has rarely been off the charts. They've also rarely been off the road. A combination of lyricism, fire and elegance has garnered the group countless performances around the nation, from the Blue Note in Manhattan, to the Newport Jazz festival in Chicago, the Saratoga Jazz festival in New York and the Jazz and Heritage Festival in New Orleans. "Being on the road is a normal feeling," says Beckenstein. "We've been on the road a good portion of every year since the late '70s. It's important for us to stay visual for our fans. Because we were there with a solid base in the beginning, we never had to compromise our sound or energy to appeal to people. We make our music for our longtime fans, though we're always glad for the new ones we attract along the way."

Spyro Gyra has tended to have a shifting membership, keeping a few regulars while adding and subtracting others as needed. Today, the touring band is made up of five members: Beckenstein as leader and saxophonist; Julio Fernandez on a mean but smooth guitar; Tom Schuman playing all keyboards; Scott Ambush handling the bottom with his funky bass; and Joel Rosenblatt providing solid drumming. Dave Samuels, one of the originals in Spyro Gyra, plays vibes in the studio. To many, it's Samuels, along with Beckenstein, who makes the sound that's heard as something of a Spyro Gyra trademark. "I think it's the sound of my horn that makes us unique," Beckenstein says, "and for a long time the sound of Dave Samuels' vibes. And there's also the sound of Julio's guitar style. It's the individuals, and the care that has been involved for a long time. These things have remained consistent."

By choosing to push the artistic envelope with each project, the band has set the standard for blending the improvisational energy of jazz with the smooth grooves of R&B and pop. Beckenstein's saxophone sound, in particular, rips through all the music with a sincere and sexy delivery. The melodies, often carried as well on Samuels' vibes, are sometimes played simultaneously, a technique that produces a distinctive and enlightening sound.

Much of that can be heard in Spyro Gyra's latest, Love and Other Obsessions. Out only a few months, the CD has been selling at a faster pace than any in Spyro Gyra's long history. The reason isn't hard to understand; it only takes a quick listen to realize that the CD offers both the band and its listeners the opportunity to explore the happy obsessions that have been part of the band from the beginning. Tracks such as "Lost & Found," "Fine Time to Explain," "Third Street" and "On Liberty Road" pay attention to Spyro Gyra's past while still containing elements of innovation. It's a formula, to be sure, but formulas aren't always bad things, especially when they attempt to guarantee long-term success by providing some long-term pleasure.

Spyro Gyra plays at 7 and 9:30 p.m. Thursday, June 1 at Rockefeller's, 3620 Washington Avenue. Tickets are $15. Call 869-8427 for info.