It’s a good time for Neutral Milk Hotel to release a career-spanning box set. The past year has seen the release of two long-gestating in-depth projects chronicling the history of the Elephant 6 Recording Co. — the collective that spawned NMH and related bands like Olivia Tremor Control, the Apples In Stereo, Elf Power, and many more — a book and a documentary film. The history of E6 can best be told through their music, though, and Jeff Mangum’s band is about to present an exhaustive collection of that output.