OXI Instruments One MKII

Moderately positive. The 8 × 16 grid of rubber RGB pads is praised as precise, low-resistance and clearly lit, and it is the main reason poly, drum and generative sequencing feel quick on it. One Hapax owner even preferred the OXI's buttons to Squarp's stiffer ones. The pads are not velocity- or pressure-sensitive. Velocity is set per step from an encoder or a bar-chart view, and bonedo notes that bigger pads would mean a much bigger box. The one consistent complaint is legibility: an owner of two weeks found the pad colours and brightness hard to read, including which sequencer is active. The Black Edition lights only each pad's outline, which some owners like for dark rooms.

“die Gummitaster drücken sich präzise und mit wenig Widerstand, sind elegant beleuchtet und gut RGB-kodiert.”

Felix Klostermann · bonedo.de (German: the rubber keys press precisely and with little resistance, are elegantly lit and well colour-coded)

“the OXI One layout works so well for poly sequences, drums, the experimental sequencers and for managing your sequences and arrangements”

Simon Sherbourne · Sound On Sound

“The colouring and intensity of the buttons is very difficult to make out at the best of time.”

MortonBumble · r/synthesizers

Sources split, and on this sequencer the workflow is the decision. Most reviewers and many owners describe a steep but rewarding curve. Sound On Sound's reviewer struggled at first, kept hunting for functions, and still concluded that once it clicks it's hard to go back. Amazona calls the interface quick to grasp but deep enough that taming it means studying the manual. Owners who moved from the MK1 say the MKII's dedicated function buttons cut out much of the old shift-combo work. A sizeable minority never got there. They describe too many shift combinations and icons to remember, notes in other octaves hidden in poly mode, controls crammed onto the left third of the panel, and an arranger and pattern workflow that fights structured songwriting. A two-week owner nearly returned it, another sold it, and a Hapax owner sent it back. Even fans list real snags: the four encoders don't line up with the four on-screen parameters (SoS), you must save a pattern before loading another or lose it, and updates have quietly changed button combinations (Alec Sea).

Moderately positive for a box that is meant to replace the computer rather than serve it. Owners use it to sketch ideas and record the MIDI into Bitwig or Logic, and one owner of the Hapax, MK1 and MKII says these sequencers complement a DAW rather than compete with one. Grooves can be imported from Ableton Live. The third-party DrivenByMoss script now supports the Mk2 as a Bitwig control surface with a full 8 × 16 clip grid. The weak spots: MIDI-file import works but with limits ('strange' in Alckemy's experience), and OXI itself does not ship a DAW-specific script.

“They actually complement daws really well tho.”

DrMinkenstein · r/synthesizers (owns the Hapax, MK1 and MKII)

“Support script for OXI Instruments One Mk1 and Mk2 controller and sequencer.”

DrivenByMoss documentation (Jürgen Moßgraber)

Sources split on the firmware and its companion app, the device's only 'software'. One camp praises how fast OXI ships: dozens of releases since launch, three new sequencer modes in firmware 2.0, a developer who answers feature requests on Discord, and fixes that often land within days. Amazona calls that pace remarkable. The larger camp, led by long-term owners, says the pace is the problem. Alec Sea, 13 months in, feels he is still in a beta test. Firmware 2.0 shipped with several old features broken. Combinations have changed without being documented, and bugs get fixed while new ones appear. Owners report bugs on Elektronauts and Reddit, and on Thomann one 1★ review says the Windows app's drag-and-drop doesn't work at all. Others report no crashes at all, and the dated complaints have mostly been answered by later point releases.

A clear strength, especially for modular rigs. Eight CV and eight gate outs, CV and clock in, TRS MIDI, USB host and Bluetooth MIDI, plus the Pipe breakout that carries every CV and gate signal into a Eurorack case over one mini-HDMI cable. Reviewers call the range of connections remarkable, and modular owners say you can load those eight CV outs with modulation. The asterisks are consistent. There is only one TRS MIDI out, so a MIDI-heavy studio wants the optional Split box (Sound On Sound's one hardware con). The USB host takes a single device, with no hubs. A USB connection can create a ground loop that detunes oscillators until you add an isolator. And one critic missed a continuous clock and adjustable CV voltage ranges.

“Oxi is fantastic for modular. 8 CV/Gate outputs that you can load up with a crazy amount of modulation.”

shhimhuntingrabbits · r/synthesizers

“You’re going to want the MIDI Split box unless you’re Eurorack‑focused.”

Simon Sherbourne · Sound On Sound

“Calibration was fine as long as the Oxi wasn’t connected to USB and once usb was in everything went off.”

qu1lym · r/modular (MKII owner, on a USB ground loop)

The strongest agreement in the record. A slim 950 g aluminium slab with a built-in battery rated at eight hours (Sound On Sound regularly got more), USB-C charging, Bluetooth MIDI and a fitted travel case. It is the reason owners pick it over the much larger Hapax, and the easy pick for anyone gigging with Eurorack. The only notes: it still needs other instruments to make sound, and OXI says high LED brightness and animations are the biggest battery drain.

“The battery is rated at a generous eight hours of use, and I regularly got more than that.”

Simon Sherbourne · Sound On Sound

“If you travel at all with Eurorack to perform live Oxi is the easy winner.”

emeraldarcana · r/modular (owns the MK1, MKII, Hapax and Reliq)

Broadly praised. The anodized aluminium chassis is called solid, surprisingly heavy for its size and luxurious to handle, with metal encoders and backlit buttons. Amazona gave its feel full marks, and bonedo calls the metal case very stable and well balanced. The QC asterisks are individual rather than patterned: one owner's power button works only some of the time, and Alec Sea's unit had a gate-output fault that OXI repaired free, leaving him without it for a couple of weeks.

“The build is solid and surprisingly heavy thanks to the metal chassis.”

Simon Sherbourne · Sound On Sound

“An der Haptik des OXI One MKII habe ich absolut nichts auszusetzen und vergebe hier, wie damals auch beim Vorgänger, die volle Punktzahl!”

Dirk E. (Xsample) · Amazona.de (German: I have absolutely nothing to fault in its feel and, as with its predecessor, give it full marks)

“my power button works 1/8 times”

Sirlordchronic · Elektronauts

Sources split, and the split is about what you compare it with. Next to the $1,299 Squarp Hapax it is cheaper, more portable and better equipped for CV. Amazona recommends it outright, and Thomann owners call it worth every penny. Against its own predecessor it's a harder sell. The MK1 still gets firmware, has most of the modes and sells used for roughly half the price. Owners of both, including Alec Sea, say the MKII is nicer to use but that the MK1 covers most of what they do. Others simply call $999 a big stack of cash for a sequencer, or note that a laptop costs less.