Indigo Girls

Indigo Girls

Can it really be more than 20 years since we first heard from the Indigo Girls? As proof, the Atlanta duo offers its 11th disc, Poseidon and the Bitter Bug, in some ways a continuation of 2006's Despite Our Differences. The gals bring back producer Mitchell Froom, who induces a rare cohesion between the rock side of Amy Ray and the moody folk of Emily Saliers. The vocalists also deliver a renewed purpose to their songwriting, as evidenced by the slinky yet haunting "Digging for Your Dream" and the mandolin/banjo-led no-compromise anthem "Second Time Around." One thing they're doing differently is offering the music in two configurations. Besides the full band album, there's the deluxe package that features a second disc of all acoustic versions, plus a bonus track. A fascinating listen on its own, Poseidon flashes back in fine fashion on how the Indigo Girls sounded two decades ago. (Sat., Stubb's, 11:15pm.)