On “Wrote Back” N-jay.52 and SaintBravo meet on a track that’s been designed to the last detail. There are blood-orange guitars, drums that sound like hollowed-out tree trunks and a low-end opaque as oil-fire smoke.  What these two musicians are after is nothing less than the belt. And what they use to get it is an analogy that juxtaposes a mothers love with their own battles for artistic supremacy. N-jay.52 ‘s voice is multitracked when the moment calls for it, but each layer is bone-dry. His stories spark smells and full-color memories; his consonants bruise. Though his tone portends regret,...