In the eight years since The Barr Brothers last released an album, Andrew has been drumming with people like Feist, Mumford & Sons, and Broken Social Scene while Brad released a solo record and underwent incredible personal change. Brad made the huge decision to get sober, which he talks about candidly in our Basic Folk interview. Anything you read about the new record, ‘Let it Hiss,’ might allude to his newfound sobriety while not mentioning it directly. The band made…