Expressive E has answered one of the most persistent requests from the synth community with the launch of the Osmose 61, a 61-key version of their groundbreaking MPE synthesizer. The French manufacturer is giving musicians an extra octave of expressive control while maintaining everything that made the original Osmose 49-key model a game-changer for keyboard players seeking deeper musical articulation.
This 61-key version addresses what many players have been asking for since day one. The original 49-key layout, while perfectly functional for many applications, left classically trained pianists and composers feeling cramped when working on arrangements that demand wider range. Two-handed playing with any kind of spread voicing quickly runs into boundary issues, and film composers orchestrating complex layers found themselves constantly shifting octaves. For anyone accustomed to the standard 61-key workstation format or coming from a piano background, that missing octave was a deal-breaker, no matter how revolutionary the keybed technology.
If you’ve been holding off because you need that full five-octave range for complex arrangements or two-handed playing, Expressive E has removed your last excuse…
What Makes the Osmose 61 Different
The Osmose 61 expands the playing surface to 61 full-size keys, giving players a full five-octave range that’s particularly valuable for complex harmonic work and extended arrangements. Everything else remains faithful to the original design: the same three-dimensional keybed that responds to velocity, press, aftertouch, pitch bend, pressure glide, strum, and vibrato, all working together to make the keyboard feel more like an acoustic instrument than a traditional synthesizer.
Weight comes in at 9.5 kg, and the dimensions measure 1060mm wide, which is notably larger than the 49-key version but still manageable for most studio setups and live rigs. The instrument maintains the premium build quality Expressive E is known for, with careful attention to repairability, a detail that should matter to anyone investing nearly two grand in an instrument.
Check out the Osmose 61 in this introductory short video:
The EaganMatrix Engine: The Elephant in the Room
As for the original 49-key version, powering the Osmose 61 is the Haken EaganMatrix engine, the same synthesis architecture found in the acclaimed Continuum Fingerboard. This is where things get interesting, and potentially intimidating. The EaganMatrix represents a fundamentally different approach to synthesis, one that feels alien even to experienced synthesists. Rather than familiar knobs, sliders, and identifiable modules like oscillators and filters, it presents a matrix-based patching system where you place mathematical constants, formulas, and control inputs at grid intersections. Think of it as a VCS3 pin matrix, but instead of pins, you’re working with mathematical expressions.
The engine itself is incredibly capable, handling physical modeling, FM, additive synthesis, subtractive synthesis, and more across 24 voices of polyphony. The sound quality is exceptional, physical modeling patches particularly shine with metallic and organic timbres that feel alive under your fingers. Hans Zimmer’s extensive use of the Osmose on the Dune: Part Two soundtrack demonstrates what’s possible when you master this instrument.
But here’s the reality: the EaganMatrix is extraordinarily complex to program. Even mathematically minded, technically skilled synthesists describe it as one of the most challenging synth engines ever created. The Haken Editor interface requires a paradigm shift in how you think about synthesis, and even simple adjustments like changing a filter cutoff or LFO rate can feel nearly impossible if you don’t know where to start. Many users, including those who’ve released albums and consider themselves adept at synthesis concepts, report spending hours watching tutorials and still feeling they barely understand the basics.
The Good News?
The Osmose ships with 580 factory presets, and there’s some excellent stuff in there. The sounds are musical, inspiring, and showcase the engine’s capabilities beautifully. For most users, the Osmose will function as a phenomenal preset instrument with unmatched expressive control. The six macro knobs per patch provide accessible sound shaping without diving into the deep end.
Expressive E acknowledges this challenge. Future firmware updates promise simplified programming tools that will make sound design more accessible without requiring users to become EaganMatrix experts. Until then, the excellent preset library and the ongoing MPE-friendly synthesizers from third-party developers mean you’ll have plenty of sonic territory to explore.
A Growing Ecosystem of Sounds
Along with its own MPE-friendly synths (such as Noisy 2 and Soliste) Expressive E has built an expanding software ecosystem around the Osmose, partnering with respected plugin developers like U-He, KiloHearts, Dawesome, Applied Acoustics Systems, and Synapse Audio. These collaborations result in the Expressive Suites, collections of MPE-optimized presets available through the company’s website.
The latest addition to this lineup is the Lounge Lizard Expressive Suite, marking the first collaboration between Expressive E and Applied Acoustics Systems. This partnership brings AAS’s legendary physically modeled electric piano into the MPE world with 100 expressive presets gathered in the “Electric Expressions” sound bank. The presets cover the full spectrum of vintage electric piano sounds, from silky tine tones reminiscent of Rhodes to bold, organic reed textures from Wurlitzer-style instruments. Every component of the original 1970s instruments is calculated in real time through Lounge Lizard EP-5’s dual modeling engine, capturing tones and textures with impressive realism. The MPE integration allows for per-note control of bend, tremolo, and volume, transforming classic electric piano sounds into something far more expressive and modern.
The MPE software landscape continues to expand beyond Expressive E’s own offerings. GForce Software recently released Map, a West Coast-inspired synthesizer with full MPE support that draws from the experimental modular designs of Serge Tcherepnin, Random*Source, and Buchla USA. With its triple oscillator architecture, dual filters, and generative polyphonic arpeggiator, Map represents another compelling option for Osmose players looking to expand their sonic palette.
The French company has also committed to ongoing firmware updates. The recent 2.1 update added 80 new analog-focused presets, new saturation and reverb algorithms, and improved the preset management system to support the expanded 2048-preset capacity.
WORTH KNOWING: The Osmose 61 comes with a 2.0.25 version of the firmware. Since it’s not available on the Expressive E’s website, users might wonder how to download the 2.1 update. Fortunately, if you just bought the Osmose 61, you already have the latest update, even though it’s listed as 2.0.25.
To clarify, the features are identical between the 2.1 update on the Osmose 49 and the 2.0.25 update on the Osmose 61.
I’ve been informed that the company plans to eventually harmonize the version numbering to eliminate confusion.
Goodbye China, Hello Poland
Perhaps the most significant change isn’t the keyboard itself but where it’s made. Until now, Osmose production was outsourced to China. With the 61-key model, Expressive E is inaugurating a new assembly facility in Poland, bringing the entire manufacturing process in-house for the first time.
This move gives the company complete control over quality assurance and allows for faster iteration on future designs. For a relatively young company, it’s a bold step that signals confidence in the product line and a commitment to European manufacturing standards. It also means better support infrastructure and potentially faster turnaround on repairs, something any touring musician can appreciate.
It’s also an intriguing sign, as it aligns with a broader trend of music tech companies reevaluating their manufacturing locations, particularly after the pandemic when supply chain disruptions underscored the risks of outsourcing to distant regions.
Now the question is, who’s next?
Osmose 61 Technical Specifications
Beyond the expanded keyboard, the Osmose 61 maintains the same core specifications as the 49-key version: 24-voice polyphony, standard MIDI (DIN In/Out/Thru), USB MIDI, two continuous pedal inputs, stereo line outputs (1/4″ TRS), and a headphone output. The Osmose also functions as an MPE MIDI controller for external hardware and software, transmitting all gestural data over MIDI.
Pricing and Availability
The Osmose 61 is out now, at €1999 / $1999. That positions it in serious professional territory, approaching the lower end of boutique analog polysynth pricing. For an instrument with this level of mechanical complexity and unique expressive possibilities, the pricing seems reasonable if not exactly affordable for casual players.
You can purchase directly through the Expressive E online store or through authorized distributors worldwide. The company occasionally offers refurbished units at significant discounts, worth checking if budget is a primary concern. A soft case with wheels is listed as “coming soon,” which will be essential for anyone planning to travel with this instrument.
Osmose 61 – Worth the Wait?
The 61-key version finally addresses the most common complaint about the original Osmose. If you’ve been holding off because you need that full five-octave range for complex arrangements or two-handed playing, Expressive E has removed your last excuse. The MPE train is leaving the station, and now there’s room for everyone.
We’ll have more on the Osmose 61, stay tuned…
