Mimicking the fat basslines that lope around its bottom ends, Natural Science by West London soul artists KV:5 is an album that rarely keeps still, working its way from the dubby “Landslide Victory Vendetta” to the minor-key folk flavors of “Treacle.” But each song gets the same tender attention to nuance, from the multi-tracked whistle on the happy-go-lucky “Flying Right” to the soaring strings on the stellar “Shelter Melter,” which recalls 4Hero at their best. The track programming may keep you off-balance, but even after many listens KV:5’s brand of scientific soul keeps serving up new rewards.