By aspect — in detail
Connectivity
Contested · 8 srcThe reason to buy it and the one genuinely contested axis. Everyone agrees on the physical I/O — Bluetooth LE (Apple BLE-MIDI), a USB-B port and a damper-pedal jack, but no 5-pin MIDI, no MIDI input, no CV and no aftertouch — and everyone agrees some wireless latency exists. Where they split is whether it matters. Reviewers and most iOS/Mac owners call it negligible and effectively as responsive as wired for composing; a real minority hear noticeable lag, and pairing can be finicky — Amazon owner Michael reports it can take multiple tries to connect and that he felt some lag. The split tracks platform (smooth on Mac/iOS, driver-dependent on Windows), distance, and use (fine for note entry, exposed by tight or live playing). Plugging in over USB removes the question entirely.
Measured
Korg's spec lists Bluetooth Low Energy (Apple BLE-MIDI compliant), a USB Type B port and an assignable switch (damper) jack — but no 5-pin DIN, no MIDI input, no CV/gate and no aftertouch. Korg's own support note states Bluetooth MIDI "has delay ranging from a few millisecond to a few tens of milliseconds in comparison with USB," and that the latency rises as the distance between keyboard and device grows; wired USB avoids it.
⚠ vs. listeners — The spec sheet and Korg's note establish that some latency is physically there, but not whether it matters — that depends on your platform, distance and playing. It reads as negligible to most iOS/Mac users composing, and as a real drag to Windows users and anyone playing tight, live parts, which is why the camps stand rather than averaging to a single verdict.
Where it splits
Wireless is effectively as good as wired — latency negligible, especially on iOS/Mac57%
“And while latency – the time it takes between you hitting a key and for you to hear the sound – is usually an issue with Bluetooth devices, we found it not to be too much of a problem, getting particularly low values when playing iOS apps.”
MusicRadar
There's real, noticeable latency — fine for entering notes, a problem for tight or live playing43%
“There IS indeed latency though, and it's the first thing you notice when you press a key for the very first time.”
Eraser · Loopy Pro forum
Consistently the strongest praise after portability: Korg's slim 'Natural Touch' mini keys are rated among the best at the size, velocity-sensitive and comfortable, with the velocity curve adjustable in the free KORG Kontrol Editor. A verified owner calls them the best keybed on any mini controller he's used, and reviewers echo it. The honest caveats are that they're still mini keys — players with large fingers report stumbling on fast lines — and a minority find the velocity variation limited (they end up editing velocities in the DAW) or the keys a touch cheap. There's no aftertouch.
“It seriously feels good to play on the microKEY. Touch response is amazing and if you have any problems with playability, you could always alter the velocity curve in the Korg Kontrol editor.”
Audio Mentor
“Best keybed on any mini key controller hands down.”
Clayton · Amazon verified purchase
“Mini keys won't be for everyone”
MusicRadar
Measured
Korg specs 37 velocity-sensitive Natural Touch mini keys (three octaves), no aftertouch, with velocity response set via the KORG Kontrol Editor rather than on the unit.
Deliberately minimal, and judged on the little that's there rather than contested. The 37 gets a pitch-bend wheel, a modulation wheel and octave buttons (−4 to +4) — no pads, no knobs, no faders, no screen — plus, on the 37/49/61 only, an assignable damper-pedal jack. Reviewers who comment call the wheels smooth and the octave buttons solid; the recurring wish is for the things it omits — a couple of assignable knobs or sliders, and aftertouch. If you want hands-on control of your DAW mixer or synth parameters, this isn't that kind of board.
“its modulation and pitch wheel, are also very smooth and responsive, while the octave buttons provided a solid feel.”
Gearank
“I just wish it had aftertouch and a few knobs or sliders to midi learn.”
Loopy Pro forum
Measured
Korg specs (37-key): pitch-bend wheel, modulation wheel, octave-shift buttons (−4 to +4) and an assignable switch jack for a damper pedal. No pads, knobs, faders, display or aftertouch.
Integration
Moderate · 5 srcA simple, class-compliant controller rather than a DAW-mapping surface — there are no auto-mapping scripts or MCU/HUI control here, just Core MIDI note/wheel data. On Mac and iOS that's a plus: it's plug-and-play with no drivers. On Windows it's the single most common complaint — the wireless link needs Korg's BLE-MIDI driver, and reviewers and owners describe fiddly setup, uninstall-and-reinstall dances, and (on older iOS) firmware-update hurdles. One owner couldn't get it recognised at all on his Mac and iPad and returned it.
“Initial setup on a Mac via Bluetooth was surprisingly fast, though Windows users should be aware that they might need to install the Korg BLE-MIDI driver to get the best performance.”
SonicMetric
“I then had some problems setting the microKEY2 Air up with Windows 10. I had to install drivers provided by Korg and also use a MIDI device uninstall tool to remove some MIDI devices that I wasn't being utilized on my Windows laptop before being able to use the microKEY2 Air.”
Audio Mentor
“AVOID this half-baked product. It's a shame, because the hardware has a nice feel and appears to be of high quality, but for me it is just a paperweight that looks like a keyboard.”
John Sadler · Amazon verified purchase
Measured
Class-compliant / Core MIDI: no bundled DAW scripts or auto-mapping. USB works driverless on Mac and iOS; wireless on Windows requires the KORG BLE-MIDI Driver (Windows 8.1+), and a one-time system updater was needed for iOS 13+ support.
A generous bundle for the price, with a familiar catch. The included KORG Software Bundle collects iZotope Ozone Elements, the Skoove learning app and a set of Korg/other software synths (resellers also list Reason Lite/Ableton Live Lite and UVI content), plus the KORG Kontrol Editor for velocity-curve and MIDI-CC customisation. The consistent gripe isn't the contents but the redemption — multiple accounts, sites and installers to claim it all.
“Korg doesn't just give you a piece of hardware; they provide a comprehensive software bundle.”
SonicMetric
“While some users found the software registration process tedious—involving multiple steps and various websites—we feel the end result is worth the effort.”
SonicMetric
Measured
Ships with a KORG Software Bundle code and a USB cable; the bundle (iZotope Ozone Elements, Skoove, Korg and third-party instruments) plus the free KORG Kontrol Editor are download-only and claimed through Korg's license center.
Portability
Strong consensus · 5 srcThe whole point, and the least contested thing about it. At 565 × 139 × 54 mm and about 1.0 kg it's a thin three-octave slab that fits a laptop bag or an airplane tray table, and it runs either off USB bus power or ~30 hours on two AA batteries (it auto-powers-down after four idle hours to save them). For a truly cable-free iPad or laptop rig, reviewers treat it as the reference answer.
“The physical footprint is so narrow that it fits on a standard airplane tray table alongside a tablet, making it a perfect companion for touring artists.”
SonicMetric
“a great little keyboard controller, equally at home in your backpack as it is on your crowded desk.”
MusicRadar
Measured
Korg specs the 37-key at 565 × 139 × 54 mm and 1.0 kg (without batteries), powered by two AA batteries wirelessly (approx. 30 hours, alkaline; <100 mA) or USB bus power when wired.
Light plastic that most owners and reviewers find sturdier than it looks — a 37-key owner calls the body solid and un-hollow, and reviewers note a reassuring chassis, better than Korg's flimsier nanoKEY. The minority report is that the plastic feels light or toy-like and that the USB port can feel flimsy. No broad QC pattern shows up in the set beyond the Bluetooth-driver headaches.
“It's unbelievably light, plastic but the main body of it still has a sturdy feel.”
Cigz · Amazon verified purchase
“There is a reassuring sturdiness to the chassis—as one user noted, it doesn't feel hollow and there is no wasted space in the design.”
SonicMetric
Positive, with the caveat baked into the name: you're paying a premium for wireless. Around $130, reviewers rate it a genuinely useful, playable travel controller; the dissent is that the price could be lower, and that if you don't need Bluetooth the wired microKEY 37 costs far less (about $80) while a fuller-featured board like the Akai MPK Mini adds pads and knobs near the same money. Its value case is strongest as a specifically wireless three-octave board.
“The Korg microKEY is a MIDI controller that is worthy of being mentioned. It's a very playable MIDI controller and I can see myself making music with it seriously.”
Audio Mentor
“Price could be cheaper.”
Eraser · Loopy Pro forum
