The new Arturia KeyStep 37 mk2 expands on one of the most loved compact sequencers in modern music production, adding Mutate and Spice generative tools, a new OLED interface, deeper CV control and expanded physical playability for hybrid, DAW and modular setups.
Key Features
- 37 slim keys with velocity, aftertouch and 39-note LED light guide
- Upgraded sequencer with pattern chaining and unquantised recording
- Mutate and Spice generative tools with Phrase Arpeggiator
- OLED screen with clickable encoder and four additional control knobs
- Expanded CV/Gate connectivity including Mod 2 output and USB-C
There’s a particular kind of magic that happens when a compact keyboard stops feeling like a controller and starts feeling like the brain of your setup. The Arturia KeyStep range has always lived in that space. Small footprint, serious sequencing chops. With the KeyStep 37 mk2, that identity feels even more focused.
At first glance, the physical updates are subtle but meaningful. You’re working with 37 slim keys featuring velocity and aftertouch, plus a 39-LED light guide running above the keybed. That LED strip isn’t just cosmetic. When you’re experimenting with scale modes, building generative arpeggiator patterns or performing in a darker live setting, visual feedback becomes part of the instrument.
The addition of four extra encoders, two new buttons and an OLED screen with a clickable encoder shifts the workflow into something that feels far more performance-ready. Instead of leaning heavily on shift functions, you’ve got clearer navigation and more direct access to deeper parameters.
Sequencing That Feels Less Mechanical
The upgraded sequencer is where the KeyStep 37 mk2 really separates itself. Pattern chaining allows you to link multiple sequences into evolving arrangements, which means you’re no longer thinking purely in 16-step loops. For hardware producers and live performers, that opens up the possibility of building full track progressions without relying entirely on a DAW.
Unquantised recording is another welcome addition. Being able to capture natural timing instead of locking everything rigidly to the grid changes the feel dramatically. If you’re chasing groove rather than perfection, this matters.
The arpeggiator has also grown more adventurous. Beyond classic up/down patterns, Phrase and Pattern Arpeggios introduce more generative behaviour. Rather than fixed note orders, they loop phrases built from what you’re holding, creating evolving motifs that feel alive rather than repetitive.
Mutate and Spice: Controlled Evolution
The headline additions are Mutate and Spice.
Mutate transforms a sequence or arp instantly. Sometimes it’s a subtle shift. Other times it feels like the pattern has taken on a new personality entirely. For live sets built around hardware and looping ideas, that kind of one-button evolution can be incredibly powerful.
Spice works alongside Mutate, injecting controlled randomness into rhythms. It’s the kind of feature that suits long-form jams or modular explorations, where you want movement without rewriting parts from scratch.
Together, they push the KeyStep 37 mk2 further into generative territory. It stops being just a MIDI controller and starts acting more like a creative collaborator.
Built for Hybrid and Modular Rigs
Connectivity has always been central to the Arturia KeyStep philosophy, and the mk2 continues that trend. USB-C modernises the setup, while CV Pitch, Gate, Mod 1 and the new Mod 2 output make it a serious option for modular synth users.
Being able to assign modulation outputs to aftertouch, velocity, mod wheel, random per-step or pulse-per-step signals turns the keyboard into more than a note generator. In a Eurorack environment, it becomes a compact control centre.
With MIDI In/Out and Sync I/O onboard, it integrates comfortably into hardware-heavy rigs. Add a pedal input for extra expression, and you’ve got something that can sit at the centre of a hybrid music production setup without feeling limited.
KeyStep mk2 vs KeyStep 37 mk2 – Choosing the Right Brain
If you’re weighing up the Arturia KeyStep mk2 against the KeyStep 37 mk2, it comes down to how central you want this unit to be in your workflow.
The 32-key KeyStep mk2 remains incredibly compact. If desk space is limited, or you’re building a highly portable rig for travel or live gigs, that smaller footprint is a real advantage. It still delivers sequencing, arpeggiator functions and CV connectivity in a streamlined format.
The KeyStep 37 mk2, however, feels more performance-oriented. The extra five keys give you a bit more breathing room for two-handed playing. The OLED screen and additional encoders make deeper functions easier to access. Mutate and Spice add generative layers that can reshape patterns mid-performance.
If you simply need a tight MIDI-to-CV bridge and compact sequencing hub for your modular synth case, the KeyStep mk2 keeps things lean and efficient. If you want something that can anchor a full hardware live set, evolve sequences on the fly and offer clearer visual feedback, the 37 mk2 arguably feels more future-proof.
A Compact Instrument with Big Intent
What stands out most about the Arturia KeyStep 37 mk2 is how much it encourages experimentation. Scale modes keep you harmonically grounded. Chord mode opens up quick harmonic movement. Gate length control shapes phrasing dynamically. Mutate and Spice invite you to take risks.
In an era where hybrid rigs blend hardware, software and modular systems seamlessly, having a compact MIDI controller that can genuinely act as the brain of the operation feels important.
Whether you lean toward the streamlined KeyStep mk2 or the expanded KeyStep 37 mk2, it’s good to see compact sequencing tools being treated as serious instruments in the world of modern music production.
