Absence makes the heart grow fonder, the aphorism goes. For Boards of Canada, their absence from releasing music over the past seven years has left their fans rabid for something, anything from the band. Then it came — a series of codes released through various media that, when entered into a website, revealed the release of the duo’s fourth studio album. The long wait for new music and the duo’s willful obscurity about its release isn’t manipulation; it’s warranted, as part of the greater mysterious appeal of Boards of Canada, and for the fact that Tomorrow’s Harvest features some of the band’s greatest work yet. It begins sounding like the opening of a science film on “Gemini,” pointing to their early influence from Canadian nature documentaries, but “Reach for the Dead” directly follows with more epic, ominous tones. Boards of Canada have always been able to imbue their wordless music with just enough suggestion that listeners can invoke their own meaning from the music, and as such, one can’t help but think of countless awful news stories or meaningless status updates when listening to a track like “Sick Times,” which strings ghostly recorded samples of voices speaking in the background behind minor-key tones that hint at global dread. Tomorrow’s Harvest isn’t all doom and gloom, though. Even with a name like “Cold Earth,” it still the strong scent of nostalgia that carried their In a Beautiful Place Out in the Country to great heights, and their cut-up beatwork on tracks like “Jacquard Causeway” entrances. Tomorrow’s Harvest is long and loaded with great tracks, like the scenic “Nothing is Real” and pulsating “New Seeds,” which both appear in the album’s final stretch, making it the kind of record you want to spin again immediately when it’s over to let its finer points sink in. With luck we won’t have to wait as long for another Boards of Canada release, but Tomorrow’s Harvest is the kind of record you can pore over for years, rich enough to rank highly with the rest of the band’s estimable catalog.