Expressive E Osmose review: A game-changing MPE keyboard, but a frustrating synthesizer

What separates it from the Roli, though, is its formfactor. While the Seaboard is keyboard-esque, it’s still a giant squishy slab of silicone. It might not appeal to someone who grew up taking piano lessons every week. The Osmose, on the other hand, is a traditional keyboard, with full-sized keys and a very satisfying action. It’s probably the most familiar and approachable implementation of MPE out there.

If you are a pianist, or an accomplished keyboard player, this is probably the MPE controller you’ve been waiting for. And it’s hands-down one of the best on the market.

Where things get a little dicier is when looking at the Osmose as a standalone synthesizer. But let’s start where it goes right: the interface. The screen to the left of the keyboard is decently sized (around 4 inches) and easy to read at any angle. There are even some cute graphics for parameters such as timbre (a log), release (a yo-yo) and drive (a steering wheel).

There aren’t a ton of hands-on controls, but menu diving is kept to a minimum with some smart organization. The four buttons across the top of the screen take you to different sections for presets, synth (parameters and macros), sensitivity (MPE and aftertouch controls) and playing (mostly just for the arpeggiator at the moment). Then to the left of the screen there are two encoders for navigating the submenus, and the four knobs below control whatever option is listed above them on the screen. So, no, you’re not going to be doing a lot of live tweaking, but you also won’t spend 30 minutes trying to dial in a patch.

Part of the reason you won’t spend 30 minutes dialing in a patch is because there really isn’t much to dial in. The engine driving the Osmose is Haken Audio’s EaganMatrix and Expressive E keeps most of it hidden behind six macro controls. In fact, you can’t really design a patch from scratch — at least not the synth directly. You need to download the Haken Editor, which requires Max (not the streaming service), to do serious sound design. Then you need to upload your new patch to the Osmose over USB. Other than that, you’re stuck tweaking presets.

This isn’t necessarily a bad thing because, frankly, EaganMatrix feels less like a musical instrument and more like a PHD thesis. It is undeniably powerful, but it’s also confusing as hell. Expressive E even describes it as “a laboratory of synthesis,” and that seems about right; patching in the EaganMatrix is like doing science. Except, it’s not the fun science you see on TV with fancy machines and test tubes. Instead it’s more like the daily grind of real life science where you stare at a nearly inscrutable series of numbers, letters, mathematical constants and formulas.

I couldn’t get the Osmose and Haken Editor to talk to each other on my studio laptop (a five-year-old Dell XPS), though I did manage to get it to work on my work-issue MacBook. That being said, it was mostly a pointless endeavor. I simply can’t wrap my head around the EaganMatrix. I was able to build a very basic patch with the help of a tutorial, but I couldn’t actually make anything usable.