SPRINGFIELD, Mo.—Rewind.
The National Audio Company near downtown Springfield does more than backtrack the past as the largest manufacturer of cassette tapes in the world. Vintage maple desktops in the company’s first-floor office have classic pink “While You Were Out” notepads. Employees still come to offices and answer phones at National Audio, just a country heartbeat from the birthplace of Route 66.
Company president Steve Stepp is a model train buff and sings the praises of songwriter Neil Young, a long-time Lionel train collector, [...]