Arturia KeyStep 37 mk2 is a compact MIDI controller and sequencer with a 37-note velocity- and aftertouch-sensitive Slimkey keyboard, OLED display, four context-aware encoders, and full CV/Gate, MIDI DIN, and USB-C connectivity. The successor to the original KeyStep 37, with an upgraded sequencer engine, generative Mutate/Spice/Dice tools, and a new Mod 2 CV output – built for hybrid setups that combine a DAW, hardware synthesizers, and modular systems.
Sequencer, Arpeggiator, and Generative Tools
The polyphonic step sequencer handles up to 64 steps with 8-voice polyphony – stack chords at any step, add ratcheting, record real-time pitch and mod automation, and chain patterns into longer arrangements. The arpeggiator has 16 modes, from classic directional types to Phrase Arp, which remaps the sequence to the notes currently held on the keyboard. Mutate reshapes active patterns without stopping playback, with the four dedicated encoders giving direct control over probability, randomness, polyphony, and density. Spice and Dice layer rhythmic and tonal variation on top. The four mode-aware encoders automatically remap their assignments depending on the active mode – Seq, Arp, Chord, or Mutate – while the Control button unlocks parameter editing without menu-diving. A dedicated CC MIDI button provides 16 assignable CCs across 4 banks.
CV/Gate, MIDI, and USB-C Connectivity
Four CV outputs: Pitch, Gate, Mod 1, and the new Mod 2 – each assignable to aftertouch, velocity, mod strip, random per-step, or pulse per-step. MIDI DIN → CV routing lets you play a modular system from an external keyboard through the KeyStep 37 mk2 as a hub. MIDI DIN In/Out for vintage hardware, 3.5 mm Sync In/Out for analogue synchronization, and a TRS sustain/expression pedal input. USB-C is class-compliant – bus powered from a computer, iPad, or external power bank (5V, min. 100 mA). In the box: 2 m USB-A to USB-C cable, Analog Lab Intro and Ableton Live Lite licenses.
KEY FEATURES
- 37-note Slimkey keyboard with velocity and aftertouch
- 2 capacitive touch strips: pitch bend and modulation
- OLED display with clickable navigation encoder
- 4 mode-aware encoders (Seq / Arp / Chord / Mutate / CC)
- Polyphonic step sequencer: up to 64 steps, 8-voice polyphony, pattern chaining
- 16-mode arpeggiator including Phrase Arp
- Generative tools: Mutate, Spice, Dice
- Chord and Scale modes – custom voicings, global or per-pattern scales
- 4 CV outputs: Pitch, Gate, Mod 1, Mod 2 (new in mk2)
- MIDI DIN In/Out, 3.5 mm Sync In/Out, USB-C MIDI
- TRS input: sustain or expression pedal
- LED strip above keybed – visual feedback for sequences, banks, and scale context
- USB-C bus power (5V / min. 100 mA) – no external PSU required
- Includes: USB-A to USB-C cable, Analog Lab Intro, Ableton Live Lite
TECHNICAL SPECIFICATIONS
- Keyboard: 37 Slimkey keys, velocity + aftertouch
- Strips: 2 × capacitive (pitch bend, modulation)
- Display: OLED
- Encoders: 4 × mode-aware + 1 × clickable navigation encoder
- Sequencer: 64 steps, 8-voice polyphony, pattern chaining, ratcheting
- Arpeggiator: 16 modes
- CV outputs: 4 × 3.5 mm (Pitch, Gate, Mod 1, Mod 2)
- MIDI: 5-pin DIN In + Out
- Sync: 3.5 mm In + Out
- USB: USB-C (class-compliant, bus powered)
- Pedal input: TRS (sustain / expression)
- Power: USB-C 5V / min. 100 mA (no external PSU included)
- Dimensions: 550 × 147 × 35 mm (21.7" × 5.78" × 1.38")
- Weight: 1.09 kg (3.5 lbs)
