By aspect — in detail
Sources split, and the split tracks who is holding it. Reviewers working from review units describe the most expressive keyboard action available — deep two-stage travel, lateral vibrato, and gestures that land within minutes rather than weeks. Owners who bought one report the same action tiring the hands over long sessions, fighting fast or percussive traditional technique, and occasionally clacking as released keys snap back. Both sides agree the surface itself is hard plastic; the “spongy” impression comes from the damper under each key, and the sensitivity is deeply adjustable.
Measured
A 49- or 61-key keybed with per-note control over tap, press, pitch bend, vibrato, shake, strum and expressive note-off (Expressive E specs). Sound On Sound measured a standard 165 mm octave width and 154 mm of playable white-key length, with about 9 to 10 mm of initial travel to a bed of resistance and roughly 10 mm more beyond it, plus about 3 mm of lateral float — where MusicTech cites an official aftertouch figure of seven millimetres.
⚠ vs. listeners — One verified buyer calls the action extremely stiff with almost no rebound; a long-term owner says sensitivity can be set so high that merely brushing a key sounds a note. Both are accurate — the note-on threshold, the velocity and pressure curves, and a lateral stabilization amount are all user-configurable and savable per preset, so two players can meet genuinely different instruments on the same hardware.
Where it splits
the most expressive action on the market, and intuitive from the first minute79%
“If you have even a modicum of keyboard technique then all the main, musically useful Osmose gestures are very easily achieved.”
Robin Bigwood, Sound On Sound
the resistance curve fights traditional technique and tires the hands21%
“I found the odd resistance curve of the keys to be more of an issue than the side to side wobble. You can expect your fingers to get sore if playing for prolonged periods.”
Walrusbongo, Gearspace
Connectivity
Strong consensus · 4 srcThe quiet win, and the strongest agreement in the record. One USB-C cable carries power and MIDI to a computer; a second USB-C socket lets you power the unit separately and keep the data line clean, and reviewers found it undemanding about what supplies it — a phone charger or a powered hub both worked. Full-size DIN MIDI in and out survive from the Osmose, so it drives hardware without a computer in the chain, and two assignable quarter-inch pedal inputs calibrate to most pedal types. The only loss versus the original is the proprietary DIN mode for Haken's CV converter.
“Power is supplied via USB-C, meaning that you can plug it directly into your computer for both data/MIDI and power connectivity.”
Roland Schmidt, MusicRadar
“The controller draws power via USB-C, with an additional power-only USB port for keeping the data line clean.”
Adam Douglas, Attack Magazine
Measured
DIN MIDI In, DIN MIDI Out/Thru, USB-C and two assignable pedal inputs, powered by USB-C Power Delivery at 5 V / 3.0 A (Expressive E specs). The DIN pair can be switched in software to act as a plain 1-in/1-out MIDI interface for the computer.
Near-unanimous praise. A white aluminium top panel over a black metal base, made in Expressive E's own Polish factory, and every reviewer who handled one reached for the same register — exemplary, off the charts, built like a bulldozer. The dissent is a single early buyer who reported a sticking D4 key firing random notes and imprecise encoders; the other verified buyer called the construction absolutely high-grade. Worth noting as a first-batch data point rather than a pattern, and the white finish is expected to show grubbiness over time.
“The build quality itself is exemplary.”
Roland Schmidt, MusicRadar
“for that ticket price you get something built like a bulldozer”
Clovis McEvoy, MusicTech
“the build quality is off the charts”
Adam Douglas, Attack Magazine
Measured
White aluminium top with a black metal base, manufactured in Poland by Expressive E (Expressive E specs); Sound On Sound describes a single coated-aluminium sheet forming the upper, rear and front panels with textured plastic on the remaining sides.
Integration
Contested · 7 srcSources split on how far the integration actually reaches. In its favour: automatic DAW detection, transport, track and device navigation, mixer control and hands-on Ctrl-e preset browsing, all of which reviewers found genuinely quick to learn. Against it: that mode covers exactly four DAWs, one reviewer found it still incomplete on pre-release firmware, another needed several restarts before the plug-in appeared, and there is no multi-zone mode for driving several instruments at once. The sharper limit is upstream of the DAW — the two-zone key travel is built around MPE pressure, so plain-MIDI use needs a hard strike for high velocity and a full press for aftertouch, and buyers whose libraries are Kontakt or Omnisphere report getting much less out of it.
Measured
Three switchable configurations — MPE controller, traditional MIDI controller and DAW controller — with DAW integration listed for Ableton Live 12+, Cubase 15+, Bitwig Studio 5+ and Logic Pro 12+ (Expressive E specs). External-MIDI presets cover MPE, multi-channel, poly aftertouch and classic keyboard, the last of which triggers notes lower in the key travel and disables key pitch bend.
Where it splits
deep, automatic DAW control that keeps your hands on the keyboard59%
“Well-implemented DAW integration”
Clovis McEvoy, MusicTech
the reach is narrow — four DAWs, and non-MPE instruments get much less from it41%
“Full DAW control is limited to just four DAWs at launch.”
Robin Bigwood, Sound On Sound
Software
Contested · 6 srcThe bundled Ctrl-e plug-in divides opinion more sharply than anything else here. It hosts nine commercial engines — Dune 3, Phase Plant, Vital, Zyklop, Myth, Kontrast, Maps, Multiphonics CV-3 and Noisy 2 — with 900-plus presets pre-mapped to the keybed and eight macros each, and if you already own one of the full versions it exposes that synth's real interface. One camp treats that as a large and genuinely generous part of what you are buying. The other finds the presets uninspiring, the editing shallow, the library skewed to synthetic rather than acoustic sounds, and the plug-in itself slow to load and prone to crashing on preset changes.
Measured
Ctrl-e is included at no extra cost and carries 900+ presets with eight pre-mapped macros each (Expressive E specs). Sound On Sound lists the nine hosted engines and their preset counts, from 30 apiece for Dune 3, Kontrast, Myth and Maps up to 350+ for Vital; the installer is about 2 GB. There is no standalone version at launch — it runs only as a VST3 or Audio Unit inside a DAW.
Where it splits
a generous, well-made instrument library that shows the keybed off71%
“Some really fabulous presets lurk amongst all these synths, spanning a huge range of varieties and styles.”
Robin Bigwood, Sound On Sound
the weak link — uninspiring presets and the buggiest part of the package29%
“Ctrl-e instruments are lacklustre”
Clovis McEvoy, MusicTech
Consistently the weakest part of the package, and sources agree on it. Six clickable encoders, a seventh knob, nine buttons, a 4.3-inch colour screen and pitch and modulation sliders sound reasonable until you find that outside DAW-control mode only the two sliders and two pedal inputs emit user-defined CC messages — fewer assignable hands-on controls than budget controllers a fifth of the price. Reviewers also found the menu hierarchy unintuitive at first, the encoders over-sensitive to speed when tweaking macros, and the side-to-side key gesture hardwired to pitch bend with no option to reassign it.
“Moreover, navigation via the display is through six infinite and clickable pots and five buttons”
Roland Schmidt, MusicRadar
“Side-to-side playing gestures are locked to pitch bends”
Clovis McEvoy, MusicTech
Measured
Seven knobs/encoders, nine buttons, a 4.3-inch colour LCD, and pitch and modulation sliders (Expressive E specs). Sound On Sound reports the volume knob was inactive outside DAW-control duties on the review unit, and that user-defined CC messages can currently be sourced only from the two sliders and the two pedal inputs.
Portability
Moderate · 5 srcA mixed bag everyone describes the same way. In its favour, it runs entirely off USB-C — no wall wart, no power brick, and undemanding about the supply — which makes it genuinely easy to move between a desk and a stage. Against it, 10 kg for a 49-key controller and 11 kg for the 61 is heavy, there is no battery, and protection is an extra: Expressive E's own soft case shipped for the 49 first, and the existing Decksaver for the Osmose does not fit the CE.
“Weight: 10 kg (Osmose CE 49) / 11 kg (Osmose CE 61)”
MusicTech, key features
“Just had a reply from Decksaver to my question as to whether the Decksaver for Osmose 61 will fit the CE”
Quatschmacher, Gearspace
Measured
10 kg / 22 lbs at 9 × 30 × 89.5 cm for the 49, and 11 kg / 24.3 lbs at 9 × 30 × 106 cm for the 61, powered by USB-C Power Delivery with no battery option (Expressive E specs).
Sources split, and the two sides are pricing different objects. One camp prices it as an instrument: $999 buys a keybed nothing else offers plus nine commercial synth engines, and it undercuts the Osmose synth by $800 while arguably beating it on timbral range. The other prices it as a controller, where $999 buys far more knobs, faders, pads and screens elsewhere, and points at the older question of whether per-note expression survives contact with an actual session — MPE controllers have a long history of ending up unused. The two buyers on record both concluded they wanted a conventional master keyboard instead.
Where it splits
priced like the instrument it is, and the cheapest way into this keybed76%
“For those who have the skills, ambition, and bank balance, Osmose CE is the MIDI controller of the moment.”
Clovis McEvoy, MusicTech
a lot of money for expression you may never actually use24%
“We’ve had this sort of expression in the ROLI Seaboard and other MPE controllers, and I get the feeling these end up gathering dust in forgotten corners of the studio.”
Robin Vincent, gearnews
