Rising from the ashes of Dischord's Bluetip and early hardcore heroes Garden Variety and Swiz, Retisonic rocks in the most J Robbins (Jawbox, Burning Airlines)-produced of ways. Although its crunchy, hand-clap-and-tambourine-embellished party tunes aren't as gratuitously riffy as, say, AC/DC, the sentiment's certainly there. Bass lines rise to mirror guitar structures, the drummer pours the fills with a heavy hand, and the ax action alternately jolts and soothes. But Retisonic might have carved these cuts a little too Lean. It's great to get back to basics, but it's usually a good idea to pull out a handful of new stops as well. Instead, Retisonic sticks with its warm but well-worn framework. Not that Lean Beat disappoints -- the duo keeps its tunes gritty, crisp and quick-moving. It's just that what's being done here has been done much better, often by Retisonic's own producer.