"I like traveling," says band leader Gene Mayl, "and I have one rule -- if I haven't been there, I have to go." That rule has taken Mayl into every state except Hawaii since he first formed his Dixieland Rhythm Kings in 1948.

The bass- and tuba-playing Mayl estimates that about 50 musicians have passed through his band. "The guys come and go," he says, "but they do come back. My proudest thing is the old-timers who have been with us -- Georg Brunis, Max Kaminsky, Gus Johnson."

Mayl's six-piece DRKs will play a concert-dance for the Potomac River Jazz Club from 8 p.m. to midnight Saturday at the Marriott Twin Bridges. Ernie Carson will be on cornet, Gene Bolen on clarinet. For information, call 698-PRJC.

Mayl's current six or eight times a month out from his Dayton, Ohio, base is a lark compared with tours of past years, when he would roll up six months of one- and two-nighters. "My idol was always Duke Ellington," muses Mayl, "and he was a one-nighter guy too. Some bands are highly regimented, but Duke's band was loose as a goose.

"I remember standing by him at a date in Indianapolis and they were closing that particular tour. They had seven days off and they started again in Phoenix. Duke said, 'Nine p.m., something, something, Phoenix, Arizona. Good evening, gentlemen' and he turned them loose and left.

"I thought that was beautiful."