JD Simo and Luther Dickinson will perform their own version of amplified American roots music at 6:30 p.m. Saturday at Flat Iron Crossroads, 7709 Flat Iron Road, Gloucester. They will be joined by drummer Adam Abrashoff. Doors open at 5:30 p.m. with Small Town Burger food truck and beer, wine, and soft drinks at the FIX Bar. Tickets are $25 online, available at flatironcrossroads.com. They will be $30 at the door. Children 12 and under are free of charge. About the band JD Simo and Luther Dickinson are building their legacies individually as solo artists, sidemen, songwriters, and guitar heroes, but “together, they’re a force to be reckoned with,” said a press release. The duo’s partnership began onstage, where the two men first shared the spotlight as touring members of Phil Lesh and Friends. Before that, Simo had built an audience with his solo appearances and as a session musician for Jack White, Beyonce, Baz Luhrmann’s movie “Elvis.” He had also contributed to the score, soundtrack...