It's no surprise that dubstep's boundaries should prove as porous as those of every other electro-dance genre; the more popular it gets, the fuzzier its lines of demarcation become, and the world's a better place for that. But few artists as closely associated with dubstep are stretching its definition quite as boldly and fruitfully as Starkey, whose second album is basically a celebration of everything electro and bassy. It refers back frequently to the dubstep verities; there are plenty of lurching, off-kilter rhythms paired with squeaky synthesizers ("Spacecraft," for example, or the exceptionally weird "Fourth Dimension"), but there are also some excursions into the street bass sound (notably "Murderous Words," which features a nicely swaggering performance by Texas-based MC Cerebral Vortex) and also some startlingly pretty moments that sound like a cross between dubstep and '80s synth pop. The album-opening "OK Luv" is oddly light in both texture and groove, and "Stars" (featuring the wonderful singer Anneka) would be lovely in a very straightforward way if its arrangement weren't so complicated by a snowstorm of microscopic chirps and whirs. "Fourth Dimension" is worth mentioning again: with its weird, screechy, cut-up synth lines and repetitive arpeggios, it ends up sounding like a Philip Glass piece as remixed by Kraftwerk. And that really should be all you need to know.