When Kieran Hebden began to play shows in support of his 2013 album Beautiful Rewind, one of the album's shorter tracks, "Ba Teaches Yoga", became a set centerpiece. Named for his recently departed maternal grandmother, the burbling track began to dilate beyond its original three-minute length as he kept performing it, eventually nearing the twenty-minute mark by the end of the tour. There might not be a direct sonic correlation between that track and the two twenty-minute tracks that comprise the entirety of Four Tet's eighth album, Morning/ Evening, but they seem thematically of a piece. The former pays tribute to his Indian heritage, the latter displays a structure that brings to mind Indian classical music.

In the same manner that ragas pertain to certain parts of the day, Morning/ Evening has a biorhythmic specificity in mind. Both tracks move between diffuse drifts of electronic tones and skittering drum programming. The "Morning" side begins with a straightforward tap of closed hi-hats and a deep thump that sounds flat at first, before a trickier pattern of programmed drums are overlaid. A melodic swell of bass then appears, as graceful, slow-moving and almost imperceptibly evolving as what you might find in early New Age music or the works of David Behrman.

And then, just over a minute in, a bright, quivering Indian voice manifests, saccharine strings at play around her. Voices often factor powerfully into Four Tet's productions: think of the honeyed utterances of "Love Cry", the chopped pirate radio barks that underpin Beautiful Rewind, or the startling reconfiguration of J. Lo's "Ain't It Funny" on "Pyramids". But the loop of famous Indian singer Lata Mangeshkar, whose voice has adorned thousands of Hindi films over a seven-decade career, startles upon its appearance. It remains foregrounded for much of the duration of "Morning", receding around the eight-minute mark for some of Hebden's most complex drum programming, then reappears halfway through. In using a famous Indian playback singer, which he no doubt grew up hearing in his household, Hebden gives the track an opulent yet pensive feel, which in turn gives "Morning" emotional depth.

"Evening" picks up where "Morning" left off, with a coffee percolator of a beat that never quite solidifies, instead leading into the kind of tones that recall early electronic music pieces like Morton Subotnick's Silver Apples of the Moon. Hebden allows each element plenty of space to breathe, striking a balance between the abstract and the accessible. Another wordless voice comes into focus about five minutes in, though my ears can't tell if it's Mangeshkar or another Hindu devotional chant.

At around the twelve-minute mark, amid chimes and gentle digital processing, "Evening" drifts into near-silence, but just as you rise to play something else, it returns: a hi-hat figure arises, amid shimmering electronics and a kick. The inverse of "Morning," the last five minutes of "Evening" gather velocity and strength, to where it seems everything is converging on a climax and payoff for this slow twenty-minute build. But right where a release might be expected, everything fades back out instead: You sense a desire to make a grand statement, but the dramatic dissolve doesn't quite stick the landing.

Nonetheless, Four Tet's position in the electronic landscape is solidified: He's able to work on the experimental fringe when he wishes, or collaborate with Burial, Jamie xx and Skrillex. Even news of a possible Diplo team-up doesn't cost him credibility. The scope and ambition of Morning/ Evening is profound, and will hopefully inspire producers to take bigger chances and not be satisfied with pop- or club-friendly lengths. Even where Morning/Evening doesn't quite work, it's daring and expansive.