At Gibson Guitar’s largest manufacturing facility, in Nashville, the plant manager, Johnny Alexander, unracks a just-built Les Paul Standard electric guitar. He slowly rotates it, light flashing on the undulating grain of its curly maple wood top. “That’s gorgeous,” he declares, showing off the wood. “That’s Mother Nature at her finest.”

Gibson is a 118-year-old company with annual sales nearing $500 million. Along with the Fender Telecaster and Stratocaster, its electric Les Paul and SG models are essential to rock ’n’ roll. Jimmy Page, Keith Richards, and Chuck Berry play Gibsons, as did Scotty Moore, T-Bone Walker, and hundreds of other greats. Gibson readily sells this tradition—a replica B.B. King “Lucille,” say, for $5,175, or an Eric Clapton 1960 Les Paul for $8,468. When Kiss guitarist Ace Frehley was in Nashville in December to introduce the Ace Frehley “Budokan” Les Paul, he raved about his Gibsons—many of which he’s modified to do such things as shoot rockets or spin like a pinwheel. “They’re made from the best materials, and the angled headstock gives you sustain forever,” Frehley said. “I’ve dropped the guitars dozens of times, and they’ve never let me down.”

The 130,000-square-foot Nashville facility builds 680 electric guitars daily, along with every component. Guitars of all colors and starburst shades stream down from the rafters on conveyors. Les Pauls and Flying V’s hang in glittering clusters to dry. The sweet smell of sawdust fills the air.

Returning the Les Paul to its rack, Johnny Alexander notes how workers there glue the necks of the guitars onto the bodies. On other company’s electric guitars, the necks are bolted on, but Gibson builds its electric guitars like most acoustic ones. It’s a slightly more expensive process, which they say produces a resonant, warmer tone. Both acoustic and electric guitars are constructed from slow-growth “tone woods,” species of wood with distinc...