Bluegrass Music from 'Del and the Boys' Melissa Block talks to bluegrass master Del McCoury and his son Ronnie. Del McCoury got his big break in the early 1960s, when he was hired by legendary bandleader Bill Monroe to sing tenor and play guitar. McCoury started his own band a few years later. The group's current lineup includes two of his sons, Ronnie on Mandolin and Rob on banjo. The Del McCoury Band has a new CD called Del & The Boys.