A return to a more time-honored approach to bluegrass revitalized their career, which over the next 30 years found them consolidating their place alongside pioneers of the genre like Mr. Monroe and the Stanleys. They were inducted into the International Bluegrass Music Association’s Hall of Fame in 1994.
Sonny Osborne retired from performing in 2005, after suffering a shoulder injury, and died in 2021. Bobby, who had previously undergone quintuple bypass heart surgery, formed a new group, Rocky Top X-Press, with his son, Bobby Jr. (known as Boj), and continued to perform and record.
Besides Bobby Jr., Mr. Osborne is survived by his wife, Karen Osborne; two other sons, Wynn and Robby; a daughter, Tina Osborne; a sister, Louise Williams; five grandchildren; and six great-grandchildren. He lived in Portland, Tenn., another suburb of Nashville.
Much has been made of the innovations in production, arrangements and repertoire that the Osbornes introduced to bluegrass. Less, however, has been said of how Mr. Osborne, whose syncopated, lyrical playing was inspired by the jazz-derived solos of old-time fiddlers, broke new ground as a mandolinist.
Speaking to the website Bluegrass Situation in 2017, he explained: “Since I always liked fiddle tunes and the mandolin is tuned like a fiddle — and I was good with a flat pick from guitar — I got completely wrapped up playing fiddle tunes with the mandolin.”
In the process Mr. Osborne earned a reputation as one of the first bluegrass mandolin players to expand the instrument’s vocabulary beyond what Mr. Monroe, the father of Bluegrass, had established early on.
Alex Traub contributed reporting.