Something felt sketchy about Quaristice, Autechre’s most recent album. Literally, much of the album’s 20 tracks—shorter than the usual fare for duo Sean Booth and Rob Brown—felt like they could have gone on longer and to more expansive and intricate conclusions. It seems that Autechre saw this potential as well, and numerous alternate versions of the Quaristice material have been released just a scant few months later, complementing the proper album. These have included a limited edition, album-length bonus disc, a Japan-only EP, and now 13 new mixes available as either a series of four EPs, or all together as Quaristice.Quadrange.ep.ae.

Like the bonus disc, Quaristice (Versions), the mixes on Quadrange are, by and large, exponentially longer than their proper-album counterparts. It’s a move that takes the shorter, more sparse ideas of Quaristice and applies the minimalist evolution that has characterized Autechre since 1995’s landmark Tri Repetae. There’s a level of restraint here, however, and in all the Quaristice-related material, that hasn’t been felt in the group’s productions since 1994’s ambient classic, Amber. The rhythmically precise sequences of clicks, ticks, and other sonic detritus are messier and scaled back here, as Quadrange instead finds Autechre exploring simple repetition and atmosphere. Ironically, the result is both more experimental and simultaneously more accessible than the previous two Autechre albums, 2005’s Untilted and 2003’s Draft 7.30.

Nowhere is the sense of space and cycling more on display than with “Perlence subrange 6-36”. Like the best Autechre remixes, it deviates far from its source material, drawing loosely on the themes of the three-minute original to produce an hour-long excursion in ambience. Swimming in reverberation, a basic drum beat and two-note bass pattern slug through the most minute and gradual of changes. This is ambient music in the sense that Brian Eno envisioned it—after a while, the sequence easily fades into the background, leading the listener to subconsciously accept the changes in the phase of the noise hit, or the length of the reverb tails, or the velocity of the bass drum. It’s machine-like and synthetic, to be sure, but its sparse atmosphere and sheer length paint the distinct sonic picture of a work built from human emotions.

Quadrange works best when it applies the “Perlence subrange 6-36” formula, scaling back the percussion in favor of warm textures. The cavernous hits on “Perlence Suns” descend in pitch as they fade away, suggesting decay and fragility. Meanwhile, the ominous minor harmonies and dissonances on “notwotwo” appear suddenly before giving way to murkier passages, climbing and descending aural peaks.

A little more than half the tracks on Quadrange place percussion sequences front and center. In interviews about Quaristice, Autechre claimed to be moving further and further away from the computer-based precision of their late ‘90s output. The rawer, fuller drum sounds certainly support this theory, as the punching noises on “Tkakanren” devour the meandering synth line. The beats here aren’t what we’ve come to expect from the Autechre of old, however, as the duo eschew tight polyrhythmic structures for messy, delayed splashes and squelches. “9010171-21” plugs along a basic, 4/4 acid beat, while bursts of sound interrupt the rhythmic lock at decidedly imperfect and improvisatory intervals—this is “free glitch”, if you will. Never before has it sounded more like Autechre are recording live.

If one had to describe Quadrange with one word, “slow” might do the trick. Very few of the pieces here assault the listener, and the more frantic tracks from Quaristice, such as “Steels” or “fole3”, are notably absent from this batch. When the more energetic ideas do appear, it’s often with a lethargic tempo, such as “The Plc ccc”, which is basically “The Plc” from Quaristice chopped and screwed. Further down this line, it isn’t surprising that “Perlence” is the track that appears most, in five different versions. Bearing a latter half of almost frustratingly skittering beats, it is the best example from the proper album of the dominant work ethic on Quadrange.

For years, Booth and Brown have professed their love for dub music. With Quaristice and its plethora of ideas, Autechre have found a perfect jumping-off point for their own extended exercises in the traditional dub practice of “versioning”. At almost 150 minutes, Quadrange boasts nearly half the number of tracks and twice the length of Quaristice. It’s a simmering exploration of Autechre at their most spacious, and further demonstration of the diversity and profundity of their sound.

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