MIDI ControllerOverreview

Arturia KeyStep 37 mk2

The KeyStep everyone had finally gets a screen and real encoders — and whether that's an upgrade or a loss of the immediacy that made the original is the whole argument.

76/ 100
Review score
19 sourcesUpdated
$199Typical US price

Score aggregates reviewer opinions across topics.

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Arturia KeyStep 37 mk2

The short version

What to know.

A compact 37-key hybrid controller and standalone sequencer, around $199, built to drive modular, hardware and a DAW from one slim keyboard. Sources broadly agree on its connectivity — USB-C, 5-pin MIDI In/Out, four CV outputs whose Mod outs now double as LFOs and envelopes, sync I/O and a power switch — on its bus-powered portability, and on the generative Mutate/Spice/Dice tools and the seq-to-arp workflow being genuinely fun. Opinion splits on the control surface: most reviewers find the four mode-aware encoders and OLED make deep editing hands-on and cut menu diving, while a minority of original-KeyStep owners miss the physical mode knobs, the one-hand MIDI-channel switch and the big BPM readout, and call it a step back for live use. The slim keybed is widely praised as the best of its class, but a cluster of owners report aftertouch that is inconsistent key-to-key and hard to trigger. Build is called rigid and sturdy by reviewers and most retail owners, while some mk2-platform owners report an all-plastic base, a fragile power switch and early key wear. The lost DC input is the most repeated single gripe; the bundle (Analog Lab Intro + Ableton Live Lite) is a modest starter kit.

About this product

The second-generation KeyStep 37 (February 2026): 37 slim (Slimkey) keys with velocity and aftertouch, a mini OLED with push-encoder, four mode-aware endless encoders plus a Control button, 39 per-key RGB LEDs, Mutate/Spice/Dice generative tools, a 16-mode arpeggiator, a 64-pattern polyphonic step sequencer with unquantised recording and chaining, four CV outputs (Pitch, Gate, Mod 1, Mod 2 — the Mod outs can run LFOs and envelopes), 5-pin MIDI In/Out, 3.5 mm sync, a sustain/expression jack, a power switch and USB-C. Not the 32-key KeyStep mk2 (November 2025, the same engine without the four encoders, per-key LEDs, ratcheting or CV LFO/envelope modes) and not the four-track KeyStep Pro. The original 2020 KeyStep 37 has its own overreview.

Arturia's KeyStep 37 mk2 is the long-awaited second generation of the compact controller that became almost a default on hybrid desks — 37 slim keys with aftertouch, a step sequencer and arpeggiator, and USB, 5-pin MIDI and CV/Gate all at once. It arrived in February 2026, three months after the 32-key KeyStep mk2, and layers that model's rebuilt engine (a mini OLED, Mutate, Spice and Dice, a 16-mode arpeggiator, sequence-to-arp and back) with things only the 37 gets: four mode-aware encoders, per-key LEDs, ratcheting, and CV Mod outputs that can run LFOs and envelopes.

It also takes things away. The original's three physical arp/sequencer knobs, its one-hand MIDI-channel switch, its DC power socket and its metal base plate are all gone, replaced by buttons, a small screen and USB-C. Reviewers were near-unanimous that it's a richer, more capable instrument; a vocal minority of long-time KeyStep owners argue it traded the thing they loved for depth they didn't ask for.

A good fit for

  • Hybrid and modular setups that want one small keyboard to drive a DAW, hardware synths and Eurorack — the CV Mod LFO/envelope modes are unique at the price
  • Players who compose from sequences and want generative variation (Mutate, Spice, Dice) on tap
  • Anyone choosing between the 32- and 37-key mk2 who values encoders, per-key LEDs and ratcheting over $60
  • Sketching and desk work where slim keys with aftertouch are enough

Think twice if

  • You switch MIDI channels constantly on a dawless rig and relied on the original's one-hand Shift+key switch
  • You need a big, glanceable BPM display or physical mode knobs on a dark stage
  • Aftertouch is your main reason to buy — try a unit first, or plan on a return window
  • You need a DC power input, full-size keys or polyphonic aftertouch
  • You have a working original KeyStep 37 and mainly use it as a keyboard/arp — the upgrade case is thinner

The reviewer consensus

Agreement &
disagreement.

3 / 8topics divide opinion
softwareportabilityintegrationconnectivityvaluekeybedcontrolsbuild
2 Strong agreement3 Mostly agree3 Divided opinions

Common ground6

  • Class-leading connectivity for the size: USB-C, 5-pin MIDI In/Out, sync I/O, a sustain/expression jack and four CV outputs — with Mod outs that double as LFOs and envelopes
  • Bus-powered, slim and light (1.09 kg) — genuinely backpack-ready
  • The generative Mutate/Spice/Dice tools and the sequence-to-arp-and-back workflow are fun and inspiring

Points of contention4

  • Control surface: hands-on depth via mode-aware encoders and a screen, or a loss of the original's knob-and-shift immediacy (MIDI-channel switching now needs a menu; the BPM readout shrank)
  • Keybed: praised slim keys with aftertouch as a bonus, versus owners reporting aftertouch that's inconsistent key-to-key and hard to trigger
  • Build: rigid and sturdy for its size, versus reports of an all-plastic base, a fragile power switch, squeaky buttons and early key wear on the mk2 platform

A closer look.

8 topics · 3 divided
Left: criticalRight: positiveTighter lines: more agreement

Keybed

Leans positiveDivided opinions
Reviewer sentiment13 supporting sources
CriticalNeutralPositive

Band: opinion spread · Dot: weighted average

Sources split, and the split is about the aftertouch more than the keys. The 37 slim (Slimkey) keys with velocity and aftertouch carry over from the original and are praised almost everywhere — reviewers call the bed quality and responsive, owners comparing it to the Akai MPK Mini Plus say it's the best mini keybed on the market, and having aftertouch at all is a rarity at the price. But a thread of 37 mk2 owners reports aftertouch that varies wildly from key to key and needs so much force it wrecks timing — the same complaint that dogged the original — a Thomann buyer found the bed 'nothing special', and owners of the mk2 platform can't agree on whether it feels better or worse than the 2020 bed. Everyone agrees 37 slim keys are a sketch pad, not a piano.

Measured

Spec: 37-note Slimkey keyboard with velocity and (channel) aftertouch — no polyphonic aftertouch — plus 39 per-key RGB LEDs and Octave −/+ transpose. Two capacitive touch strips for pitch and modulation (no wheels).

Where it splits
A quality slim keybed — the best mini keys in the class — with aftertouch as a rare bonus at the price80%

“The KeyStep 37 mk2 is built around a quality slimline keybed with velocity and aftertouch.”

MusicRadar
The aftertouch is inconsistent key-to-key and hard to trigger, and the bed itself is nothing special20%

“It's very inconsistent from key to key, and you have to push really hard for it to even trigger on any of the keys, let alone have any control over its magnitude.”

u/Xyttra · r/synthesizers
Link to this topic

Follow the evidence

Sources 19

1–6 of 19 sources

Read with context

Limitations & method.

As of

What to keep in mind 6

  1. A read of where opinion lands as of September 2026, seven months after launch — firmware updates and the field (a KeyStep Pro successor is widely expected) will keep moving it.

  2. Most of the press reviewed launch units in the same week; longer-term wear, switch and aftertouch reports come from owners, who tend to post when something's wrong — so they may look more common than they are, but they're consistent enough to plan around. Buy somewhere with an easy return window and check your unit's aftertouch.

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