The liner notes for Decks, EFX & 909 lists the gear used to construct this extended mix:

Technical list: Vestax PMC-50A Mixer. Vestax DCR1200PRO Isolator. Ensoniq DP/2 Effects Processor. Roland TR-909 Drum Machine. Technics SL-1200 Turntables. Stanton Trackmaster Cartridges. Roland CV Pedal.

In the list "SOME OF THE AUTECHRE HARDWARE" in their Sound on Sound interview it said that they use the Ensoniq DP/2.

Ensoniq DP/2 is pictured in the photo taken in Surgeon's studio.

http://www.xlr8r.com/gear/2014/10/in-the-studio-surgeon/

They were selling it on Facebook in 2015

An Ensoniq DP/2 unit can be seen in Stephen Street's studio, in the fifth photo. The fifth photo is captioned: A selection of Street's gear: from top, TL Audio Classic dual valve EQ and Indigo VP2051 voice processor, Empirical Labs Distressor compressor, Emu Vintage Keys and Proteus FX synth modules, Yamaha SPX900 multi‑effects, Antares ATR1 Auto‑Tune intonation processor, Novation BassStation Rack, Zoom Studio 1201 effects, Mutronics Mutator filter bank, Ensoniq DP2 effects, SPL Transient Designer dynamics processor, and two more Distressors.

List of effects at Paul Robb's studio:

Aphex Type C2 Exciter. BBE 462 Sonic Maximiser enhancer. Drawmer DL241 dual compressor. "I generally strap this across the stereo buss. At some point I'd like to get a better compressor, though." Boss SE50. Boss SE70. "I primarily use these for distortion." Digitech VFX Valve FX. "This is an awesome distortion box. It's so bright it will rip your head off." Ensoniq DP/2. "I also use this primarily for distortion. All four of my distortion boxes [Digitech Valve FX, Roland SE50 and SE70, Ensoniq DP2] are absolutely critical to me. They're indispensable. I rarely use synthesizers anymore without running them through a guitar box." Eventide H3000 multi‑effects. FMR Audio RNC1773 Really Nice Compressor (x3). "These are my new favourite boxes. They make them in Texas, and they're incredibly cheap — 179 dollars, I think it was. But they're great, and on a par with the Drawmer compressor." Focusrite Red 2 Dual EQ. "It's mostly just gorgeous looking! Everyone who comes in here notices it. It looks like a piece of candy, you just want to bite on it. The thing is, it's so intimidating to look at, you really can't tell if it's any good or not — it doesn't need to be any good! I like it, though it's not quite good enough to strap across the whole mix: the EQ3D is on a par, even though it's half the price." Focusrite Red 7 Voice Channel. "This has a mic pre, a compressor, an enhancer and a de‑esser in it, which we use for recording vocals." Lexicon MPX1 multi‑effects. Lexicon PCM70 multi‑effects. Nightpro EQ3D filter. Peavey Analog Filter. "I actually very rarely use this. I've run some loops through it to make them sound crunchy and lo‑fi and it works OK. These techno people use outboard filters all the time — it's just that this one isn't a particularly good one, and I can't justify spending a grand on something like the Waldorf DPole or the Mutator." Roland SDE1000. "I just use this for simple delays." Roland SRV2000 reverb. SPL Vitalizer. "I think this is a lot more popular in Britain than it is here. I like it, but it has so much background hiss that I can only use it in loud noisy music. The great thing about it is the way it spreads the stereo fields, it's got some kind of phase." TC Electronic M2000 multi‑effects. Yamaha SPX90 multi‑effects. "This was the first effects box I ever bought and it's totally on its last legs. I keep it for its stereo split program, because it sounds so grainy and nice."