On District Line, Bob Mould takes stock of a career that's taken him from being an angry, visionary punk to a respected alt-rock giant, drawing on his past while moving ever forward. "Shelter Me" finds him continuing to experiment with disco-oriented sounds, while "Old Highs, New Lows" is a sumptuous jam that actually resembles Peter Gabriel and "Again and Again" only needs a simple acoustic refrain for its take-no-prisoners excoriation of a callous ex.