There's something quite unique that happens when you get a number of voices working in unison to the same end, and that's what local group Sister Solace is all about. With 13 members—all women, their voices harmonize together to create a haunting tonal quality applied, with simple, earnest and original instrumental backing, to Appalachian and Eastern European folk tunes. Led by Gabrielle Pietrangelo—a favorite on The Coronet patio, the vocal harmony group offers a little something different and, some would rightly assert, chorale to the typical Tucson concert experience. Sister Solace performs at the Scottish Rite Cathedral (160 S. Scott Ave.) on Friday, May 13. The doors open at 7 p.m. and the show starts at 7:30 p.m. Admission is $10 at the door.