From playing shows to seeing artists like Janelle Monáe and Greta Van Fleet, Emily Saliers — one-half of the Atlanta-based duo Indigo Girls, along with Amy Ray — has a plethora of memories that she could share about the historic Fox Theatre. And she’s about to be able to add one more.

The late singer Gregg Allman inspired many musicians like rapper Killer Mike, Emily Saliers of Indigo Girls, and Mike Mills of REM, to name just a...