The prolific Guillermo Scott Heren, sale man of many pseudonyms, is back with yet another release under his most noteworthy guise, Prefuse 73. One of the forefathers of the glitch-hop sound — an abstract, mostly instrumental and regularly angular take on hip-hop’s standard 4/4 — Prefuse builds upon an already stellar body of solid experimentalism with Preparations, again released on Warp. Guests on the record…