Taking their pursuit of severely electronified “hip-hop” global, Miami’s Merck drafts Bulgaria’s Esem for a dark ride through a mountainous amalgam of shimmering electronics and murky splatters of broken beatdowns. Unfortunately, Serial Human isn’t totally free from the usual problems that plague IDM artist albums; the good songs are truly great, while some of the others are just fine. “Tjiccli” sprightly bounces along, layering more and more complexities in a blurring hall of mirrors, and sounding completely fresh, while elsewhere, “Bleece” resembles the backing track to National Geographic Explorer. In essence, this imperfection indeed makes Esem truly human.