TEN YEARS ago, Mike Nardella saw his passion for classic rock 'n' roll and rhythm and blues evolve into a successful small-business career. But let's backtrack to Georgetown University, 1967, and the arrival of a young freshman from Rochester, N.Y.

"I was in bands in high school, a good all-American boy, quarterback on the football team," Nardella recalls. "Put together a big soul band in the early '60s. I came to Washington because I loved R&B . . . and it was the only place you could go and drink at 18 without staying in New York state." He'd promised his parents that he wouldn't play in any bands while he was in college ("I didn't"), but he still hung out at the Howard Theatre, catching the legends of rhythm and blues while that genre was still at its peak.

At Georgetown, Nardella would occasionally get up and sing with a student band called The Malibuz (which spawned minor rock star Walter Egan), but "mostly I'd go around and get drunk with the bands. At the school mixers, I noticed nobody danced until I'd get up and sing 'In the Midnight Hour' -- and I can't sing, but everybody would react." So Nardella would make tapes from his own albums and singles ("I wasn't a collector, just bought what I liked") plug a tape recorder into an amplifier and have instant party music.

Nardella was a popular man on campus for four years, but after graduation he found himself in limbo, on a waiting list for law school. He worked as a Sears customer-service man, drove a school bus, "chased girls and had a good time." Invited to a party at Mount Vernon College, Nardella ended up bringing a turntable and some records (the tape deck belonged to a friend who had gone off to law school) and the parties started all over again, getting bigger and better.

"Then I got a call from Dumbarton College. They were opening their pub in January and wanted me to come play my records. I said it was a big room, I'd have to rent some equipment, so they gave me $100 and free beer, put out some flyers saying 'Nard's Oldies.' That was the first paid show."

The manager of a local bar happened to be there and asked Nardella to fill in two nights later for a band that had canceled out. With only an announcement from the stage, the club was packed. "So we started at Chadwick's on Tuesdays, then at Whitby's, which is now Duddington's, on Thursdays and Sundays at the campus club, which was Colonel Mustard's and is now a parking lot . . ."

All told, business picked up to the point where now Nardella can (and frequently does) send out 30 disc jockeys a night, each with a set of 3,000 to 5,000 singles, to work in more than 25 local clubs (one to seven nights a weeks) and a passel of private parties. He's done more than 30,000 shows, retaining the disc rather than tape format. "I still go all with records because of the fascination that people feel when they see a guy with 45s all over the place. Most people haven't bought a 45 since they were 10 years old, they remember their older brothers and sisters having a stack of them. To see a wall of tunes . . . well, they're fascinated. And it allows for flexibility in the deejay's decisions; they can read a room, decide what they want to do with a crowd."

Nardella, who does all the buying (continuously) and selection himself, has many different sources -- auctions, private collections and companies that specialize in re-pressing old hits. With 30 sets, he obviously buys in quantity, finding that the wear-and-tear factor is better for older records than new ones. "The way they make them today, a record can last a night . . . or three years."

Nard's sticks mostly to the oldies format (with a set for country and big-band jobs). "The oldies are what people remember; they were all alive at some different place in the United States, but a particular song can bring them together in that room at that time. We're playing it more for their head than their feet."

Though he now has franchises in Boston, Fort Lauderdale and Rochester, and his Washington headquarters does shows as far away as Baltimore and Richmond (Nard's Rock and Roll Review is in fact America's oldest and largest rock 'n' roll disc-jockey service), Nardella still remembers some rough early nights. "When I started this, one of the big things I had to overcome was that people were oriented to live music and had forgotten about discothe queing. And record hops seemed to be too much of a kid thing remembered from junior high school. Disco hadn't happened, so it was a question of acceptability when people would walk into a bar and see me sitting there with two turntables and a little amp and a stack or records and they'd go, 'What are you doing? What is this?' And they'd wonder until they'd had a few beers and the whole thing would get rolling." Ten years later, it's still rocking and rolling.