(AP) — Grateful Dead founding member Phil Lesh has died at age 84. Lesh was a classically trained violinist and jazz trumpeter who found his true calling reinventing the role of rock music’s bass guitarist. He was the oldest and one of the longest surviving members of the band that came to define the 1960s acid rock sound. His thundering arpeggios, played on a six-string electric bass, intertwined with Jerry Garcia’s soaring lead-guitar solos to give the Grateful Dead a unique, often-copied but never duplicated sound. He also co-wrote several Grateful Dead songs, including “Box of Rain.”