Young artists are gathering in Nashville, so they can book shows in house venues that pop up in gentrifying neighborhoods. They're recording albums themselves or with independent producers like Jeremy Ferguson, who started mixing records in his basement before building a garage studio in his backyard. And they're organizing into an underground scene that's starting to look like a rock revolution that could one day dethrone country twang as Nashville's most famous sound.One of the launchpads of the movement is DRKMTTR, an all-ages house party of a venue west of downtown that's set in an old barbershop and flanked by clapboard houses. The volunteer-run venue has been shut down for fire-code violations in the past, and to the young fans showing up with coolers of beer, it can seem like nobody's in charge. That's the charm. "A lot of [the Nashville mentality] is anti-establishment," says Olivia Scibelli, lead singer of Idle Bloom, a band currently writing its second full-length album from Scibelli's East Nashville basement. "It's kind of about taking out the middleman." Scibelli helps run DRKMTTR, and Idle Bloom has played there in the past, but during a recent rehearsal session, the band's four members crowd into a windowless room alongside their abused equipment. We take a look inside Music City's indie, DIY scene.