Keith McMillen QuNexus RED

Sources split down the middle, and it is the decision. One camp — both magazine tests, a long-term owner blog, a dealer and a run of owners — finds the 25 silicone keys (30 × 13 mm, ~2 mm proud of the case, no travel beyond a slight compression) responsive and authentic for velocity, with usable polyphonic pressure and a tilt that, after the 2.0 rewrite, engages instantly and slides like the K-Board Pro 4's Y-axis; 'more like a gamepad or drumpad than a keyboard' is meant as praise. The other camp, of equal weight, finds exactly that the problem: the keys are too short and flat for piano technique (no raised sharps, no upper-key playing, chord fingerings that don't fit), pressure is already applied at note-on so fine aftertouch control is hard, tilt-to-pitch is hit-and-miss, and per-key response varies enough that Amazona calls it a factor you must deal with — the editor's per-key sensitivity table is the fix, and the RED is the first version calibrated at the factory. Two owners report defective sensors on RED units (three hot keys on one, keys that play by themselves on two others), and the maker's August 2026 firmware adds a boot-time sensor tare 'to reduce stuck-key false triggers'. Pre-2021 complaints about the black unit's velocity jumps and tilt bugs are dated: the 2.0 algorithm is the maker's answer, and owners who upgraded say it feels like a new instrument.

Leaning negative, with a real defence. There are no knobs, faders or display: two octave buttons, a pitch-bend pad, four preset/mode buttons and a Shift key that turns the 25 keys into a menu (numbers, note divisions, MPE/channel, CV, gate, transpose), with blinking LEDs as the only feedback. Sound On Sound calls the interface 'inscrutable' at first and the bend pad fiddly and inaccurate; owners describe 'endless shift keys to memorize', a bend button that never felt expressive, and an updated black unit whose printed labels no longer match. On the other side Amazona rates it a plus that every sequencer, clock and CV setting can be made on the device without ever opening the software, and KMI's rewritten bend algorithm (full ±8192 range, new sensitivity setting) is what turned the 2013 pad from unusable to merely fiddly. Muscle memory arrives, reviewers agree; a screen and two encoders would have spared it.

“At this point I feel I should mention the QuNexus user interface, which could be described as inscrutable.”

Nick Rothwell · Sound On Sound

“Das gute am Sequencer des QuNexus RED ist die Möglichkeit wirklich alle Einstellungen am Gerät selbst vornehmen zu können, ohne jemals die Software bemühen zu müssen.”

Markus Schroeder · Amazona.de

“I honestly can’t be bothered with endless shift keys to memorize and buried functionality.”

deastman2 · comment under loopop's review

Sources split. For the plug-in-and-play case they agree: class-compliant on macOS, Windows, Linux and iPad (Camera Connection Kit), three virtual MIDI ports (keyboard, expander, CV), four factory presets including a proper MPE preset (manager channel 1, members 2–14) that Korg Module, SWAM, stock Ableton MPE instruments and the Micromonsta 2 pick up without drama — cigilovic 'was literally able to plug this in and start triggering sounds'. The other camp is about everything past that first hour: SOS found MIDI-clock quantising hit-and-miss (arps start on the first key press, not the downbeat) and preferred letting the QuNexus be master; a two-year r/abletonlive thread describes hours lost tuning MPE tilt and a bend pad that stops working after saving a preset, with no reply from support; and the CV/gate threads — Mother-32 and 0-Coast owners who could not get a gate or changing pitch — mostly resolved to a firmware update that had silently failed over a USB hub, one to a replacement board, and one never resolved. The split tracks depth of use: DAW/iPad players land in the first camp, hardware and modular users in the second.

Mostly positive — the 2.0 firmware is the best-liked thing about the RED, the editor the least. The three-track arpeggiator/step sequencer (32 steps, 8 patterns per track, ten arp modes including pendulum, random and Brownian, dotted and triplet divisions, 5–255 BPM, each track routable to USB, DIN or CV, track 1 sequencing MPE pressure and tilt) drew 'spectacular' from MPE-forum veterans and 'very rich' from both magazines, and the fact that it was given free to owners of a 2013 keyboard — with a decal kit for the old panel — earned KMI goodwill even from critics; the editor was rewritten in Qt in 2025, open-sourced under MPL-2.0 on GitHub, and firmware is still being updated in 2026. The negatives are real but narrower: SOS finds the editor small, fiddly and dated; Amazona's minus list has its non-HiDPI interface and a firmware updater that stumbles on non-English systems; and one Ableton user calls both the editor and the manual 'a nightmare', with terms in the manual that do not exist in the software. No bundled DAW or plug-ins — the value is the firmware, not a content bundle.

“Der Sequencer im QuNexus RED bietet sehr umfangreiche Möglichkeiten.”

Markus Schroeder · Amazona.de

“It’s truly impressive how much better the QuNexus functions and feels to play now.”

wolfkabob · Poly Expression forum

“The editor window is a bit small and fiddly, and the overall design looks rather dated: this could do with an update and a design refresh.”

Nick Rothwell · Sound On Sound

“The manual is a nightmare, never had any answer from KMM, and it never behaves the same. The editor is a nightmare too.”

Tristan_Baldi · r/abletonlive

Sources split, and the split is partly by generation. Everyone counts the same ports — a USB host socket, a mini-USB 'expander' port that becomes 5-pin MIDI out with the included adapter (or in and out with the $39–64 MIDI Expander box), a gate plus three 16-bit 0–5 V CV outputs on two 3.5 mm TRS jacks, two 0–5 V CV inputs plus 5 V for an expression pedal on one TRRS jack, all usable at once — and one camp reads that as a staggering amount of I/O for a keyboard this size, the thing that makes it a hub rather than a controller. The other camp reads the same list as a bag of adapters: a standard mini-USB cable does nothing in the expander port, the CV outs need TRS-to-dual-TS splitters and the ins an obscure TRRS breakout (the $39 cable kit), it is a USB client so it cannot drive a synth's USB-MIDI input without a host box, and every unit before January 2022 has a micro-USB socket ('Wish this had USB C' is the top-voted complaint under loopop's review). Amazona measured the gate at about 4.8 V rather than 5, enough for one of the tester's synths to ignore it, and CV users report a ground-loop whine when the QuNexus and an audio interface share a computer's USB (the manual's remedy is a separate USB power supply). No Bluetooth, no battery.

The one thing nobody disputes. 325 × 84 × 11 mm and 345 g — laptop width, slimmer than most laptops, a weight Amazona calls unusually high for the size but helpful when playing — bus-powered from a computer, iPad or USB battery, with silent keys that owners recommend for travel and that one producer has carried in a backpack for five years. The caveats are the cables (SOS and an Elektronauts owner both note you end up toting adapters) and the fact that it needs a host: no battery, no Bluetooth, and the CV side wants a power source too.

“Both keyboards are light, super‑portable MPE‑capable controllers.”

Nick Rothwell · Sound On Sound

“Mit den Maßen 325 mm x 84 mm und nur 11 mm Höhe passt der Keith McMillen QuNexus RED in jede auch noch so vollgepackte Gig-Tasche, kommt allerdings mit einem, für seine Größe ungewöhnlich hohen aber beim Spielen vorteilhaften Gewicht von 345 g daher.”

Markus Schroeder · Amazona.de

“The thing works with anything, transforms any tablet, it's portable, utilitarian and fun.”

Moist_17 · r/synthesizers

Sources split between the chassis and the sensors. The case wins near-universal praise: a rigid slab with no give at the ports, keys that sit rock-solid, an ABS-polycarbonate shell that fixed the black model's notorious soft-touch coating (the maker admits the redesign was 'specifically to address quality control issues'), and long-term owners reporting seven- and ten-year-old units still working; 'virtually indestructible' is the dealer line and few owners argue. The other camp is about what is under the keys: a MIDI-OX-verified unit with three sensors that fired on their own (returned), one owner through two RED units whose keys 'get stuck down playing or play entirely on their own', a new unit that creaks and flexes on a flat desk, a CV jack that loosened after cables were left plugged in a bag, and an iPad user with two keys permanently half-lit. KMI's own August 2026 firmware — a boot-time sensor tare 'to reduce stuck-key false triggers' — is the first-party acknowledgement that this is a population, not one lemon; support, when it answers, is described as generous (replacement boards, free enclosures), but several owners say it did not answer.

Tilts positive with a vocal minority against. The case for: at $179–199 (now $249 for the identical Galaxy) it remained, in Amazona's words, the most complete and cheapest small MPE controller on the market, the only thing at the price with poly aftertouch, MPE, CV in and out, DIN out and a sequencer, and the free 2.0 update for a decade-old product made even critics warm to the company. The case against comes from two directions: hardware-sequencer buyers who point out a Keystep or SQ-64 does more sequencing for the same money, and owners who feel the whole KMI catalogue is priced at double what it should be — plus the returns and defects above, which turn a bargain into a gamble. Note that the two-octave K-Board C ($119) shares the keys and MPE; you are paying the extra for the sequencer, CV and MIDI ports, and the maker's own comparison chart says so.

“Mit ein paar Abstrichen im Bedienkomfort, aufgrund des kompakten Designs, ist der QuNexus RED immer noch der umfassendste und preiswerteste MPE-Klein-Controller am Markt und hat sein BEST BUY von 2013 somit aufs Trefflichste verteidigt.”

Markus Schroeder · Amazona.de

“never been anything like it before or since for the money”

Sean · comment on Synthtopia

“Like all KM products, this is priced at at least double for what I would pay for it.”

ZZKJ396 · comment under loopop's review