On a summer evening, students of all ages fill the twelve practice rooms in the old Nalli Building just down from the Fleetwood Diner.

Upstairs, Dave Sharp, of the jazz-funk band Dave Sharp’s Secret Seven, teaches a blues class for adults. Down the hall, parent Kris Groh waits for her young son to finish his guitar lesson before she steps in for her own mandolin session. Downstairs, local tenor saxophone great Paul Vornhagen works with a student. In the common areas, students tune up before their lessons or linger after workshops. Jazz piano student Oren Levin, twelve, peers through a window into the large first-floor practice room, where his brother, Erez, is playing drums in an improvisation class.

The improv class is taught by Alex Johnson, founder and director of the Ann Arbor Music Center and its Rock Band School. He moves from instrument to instrument, talking to each student about establishing a rhythm and a framework from which to improvise, one chord at a time.

“Being in this building is like coming home,” says Johnson later. “I used to walk over here after school when I was fourteen, and now I have a key to the door!”

Back then, in the 1970s and early 80s, this was the Nalli Music Store Annex. The Nalli family’s Main Street store sold pianos, but the Annex was the go-to hub for guitars, keyboards, and anything anyone in rock ‘n’ roll might need.

Johnson, a Community High grad who helped coordinate the first of the school’s annual “Comstock” concerts in 1984, was an Annex regular. “I bought one of my first guitars here,” recalls Johnson, sitting in his practice room, its ceiling draped with tapestries, an oriental rug on the floor, and classic rock posters on the walls. “One time, when I was fourteen, I came here to look at guitars and there was Rickey Medlocke, standing right next to me.” Medlocke played drums with Lynyrd Skynyrd in the early days, then guitar for Blackfoot.

The Annex had two recording studios, and Brownsville Station and Blackfoot recorded there. Plenty of other well-known musicians stopped in, too. “They say Stevie Wonder pulled up in his limo to talk to a keyboard guy about the latest techniques, and that another time David and Angie Bowie stopped by,” says Johnson, with a toss of his long, thick sandy blonde hair.

Johnson says he spends “seventy hours of not working a week” at his musical mecca. He moved here from a cramped 1,700-square-foot house on North Main because there wasn’t much wiggle room for the forty rock bands and more than 400 students annually taking workshops, lessons, and clinics on rock, blues, and jazz. But what really gets Johnson jazzed are the ways he can enrich his program now that he has more space. He points toward a hallway. “We’ll be installing a Rock and Roll Hall of Fame timeline,” he says, “full of photos, because we teach the history of music here along with the technical fundamentals, traditions, culture, and the theory behind it.”

If that reminds you of Jack Black’s classroom in School of Rock, you’re on familiar turf. In a building with this kind of history, the walls are always rockin’.