The Count Basie Orchestra in "A Tribute to Ella, Joe, Basie" is the first concert in the Jazz Roots series, and features vocalists Janis Siegel and Kevin Mahogany. Artists in the series will conduct clinics at local high schools, and a limited number of high school students will attend sound checks and special Q&A sessions with the performers; 8 p.m., Wednesday, Sept. 25. Tickets: $29 to $89, at Cobb Energy's box office and all Ticketmaster outlets. Cobb Energy Performance Centre, 2800 Galleria Parkway; 770-916-2800; www.cobbenergycentre.com/

Scotty Barnhart, an Atlanta native and jazz trumpet virtuoso, was a starstruck high school musician back in the early 1970s when he saw the Count Basie Orchestra perform at the Fox Theatre.

Standing outside on Peachtree Street, waiting for his parents to come give him a ride home, Barnhart suddenly saw the whole orchestra walking out of the Fox and across the street to the Georgian Terrace.

There went Freddie Green with his guitar. There went tenor man Eric Dixon, and trombonist Grover Mitchell. The teenaged Barnhart had to say something, so he haltingly introduced himself as a trumpet player at Gordon High School. The next thing he knew, he was inside the hotel lobby, chatting away with trumpeter Sonny Cohn (whose great solo embellished Basie’s timeless version of “April in Paris”) as other band members passed him plates of food.

Forgotten, in his euphoria, was a certain appointment with his progenitors. “And I look out the front windows, and I see my parents circling the block, circling the block,” Barnhart laughs now. “From that moment on, I knew I would be in the Basie orchestra.”

This week Barnhart, 48, a 20-year veteran with the band, was appointed the director, just in time to play a gig in his hometown when the 18-member group plays Wednesday at the Cobb Energy Performing Arts Centre. The evening is called “A Tribute to Ella, Joe, Basie,” and honors William “Count” Basie, who died in 1984. It features vocalists Janis Siegel and Kevin Mahogany reprising some of the songs that Ella Fitzgerald and Joe Williams made famous as featured singers with the Basie group.

Barnhart, a protege’ of Wynton Marsalis, has served the Basie orchestra in various capacities while holding down the lead chair in the trumpet section and directing his own small group. Now living in Tallahassee, he also teaches jazz at Florida State University. Ascending to the directorship is, to Barnhart, akin to picking up the baton at the New York Philharmonic after Toscanini has set it down.

“I’ve been given a great opportunity,” Barnhart said by phone during a Basie band tour stop in Tokyo, “and it’s humbling, because of the history of the organization.”

William “Count” Basie, from Red Bank, New Jersey, formed his first jazz orchestra in 1936. It became known for its irresistible swing, wild dynamics (from thunderous to pin-drop), blues sensibility and “head-charts” created on the spot.

Barnhart wants to bring back that improvisatory legacy. “These young folks, everybody wants to have sheet music in front of them, but that’s not the way it used to be,” he said. He said his musicians — and his audiences — can expect to take some more chances in the future.

“We can’t wait to be on stage to show people what we can do.”