M-VAVE SMK-37 Pro is a new 37-key USB-MIDI keyboard controller with a built-in DX-7 FM Synthesizer for around 100€.
In June, the Chinese company M-VAVE released the SMK-37 Pro, a MIDI keyboard controller featuring a built-in FM synth engine and additional capabilities. As announced and promised, I ordered the device and tested it out for you.
Here is my review and walkthrough video. It’s not yet certain whether a full written review will be published. It depends on readers’ interest and, in my case, time.
And if you’re wondering about the price, why 100€ and 70€? The 100€ is a price you see frequently on Aliexpress, so I used it for the article title. However, I actually got mine for under 80€, thanks to coupons and other discounts.
Article from June 14, 2025
When searching for MIDI controllers, you’ll likely turn to those from major manufacturers, such as Akai, Arturia, Novation, and others. If you’re looking for something more affordable, people often turn to platforms like AliExpress, Temu, or Amazon, where Chinese companies offer MIDI controllers at lower prices.
Donner and M-VAVE are brands particularly well-represented on these platforms. Yes, Donner also entered the Synthesizer and drum machine market. M-VAVE is now following suit with a hybrid product. M-VAVE has released the SMK-37 Pro, a new USB-MIDI keyboard with a built-in Synthesizer engine.
M-VAVE SMK-37 Pro
The new M-VAVE SMK-37 Pro is a new 37-key velocity-sensitive MIDI keyboard with a three-octave range. M-VAVE SMK-37 Pro has everything we know from classic MIDI controllers.
On the left side, you have classic pitch and mod wheels. Then, it has 16 RGB backlit pads with velocity and aftertouch support, eight endless rotary encoders, and 16 RGB backlit pads with velocity and aftertouch support. Additionally, it features four black faders that can be expanded to eight using the dedicated fader bank button.
M-VAVE has built a lot more into its USB-MIDI controller. First, it features a built-in sequencer that allows you to save up to eight patterns. It offers three modes: key, live, and drum, and each sequence can have up to 64 steps with swing, gate, and tempo controls.
Next, you have a built-in arpeggiator with various modes (up, down, incl, excl, random, and order) and a note repeat function.
Built-in Synthesizer
The unique feature of M-VAVE SMK-37 Pro is its built-in sound engine. It features an FM Synthesizer based on the legendary Yamaha DX-7. According to the developer, several parameters can be adjusted directly on the device, while others can be tweaked through the USB-MIDI output port.
A review of the manual reveals that the engine features 32 algorithms, allowing you to control the algorithm choice, feedback, mono/poly mode, volume, cutoff, distortion, reverb, and delay—no information is provided on the polyphony of the engine. There is also Sysex load support.
I guess the engine is based on the open-source FM Synth Dexed project, although this has not been confirmed.
On the backside, it has an ON/OFF switch, a USB-C port, a TRS MIDI output, an audio output, and a sustain/expression pedal input. According to early users on Reddit, it also offers audio over USB. As a bonus, it also comes with Bluetooth 5.0 MIDI support.
First Impression
At first glance, this appears to be a great overall package for a budget-friendly price. One thing is sure: it offers more features than the MIDI controllers of the big players. The SMK-37 Pro synth engine may not win any world championships in synthesis, but it’s nice to see that such an inexpensive controller features a built-in synth.
The M-VAVE SMK-37 Pro is now available directly from China for around 100€ (depending on coupon codes, etc.). Later, it will also be available on Amazon.
More information here: M-VAVE
Available at my partner
Pretty good deal for $100 euro. I’m guessing MKII will have poly aftertouch.
wow! with real Midi! with trs but better then without. i don’t Like the Most Midi keyboards today. Need s real Midi Din Jack.
That’s a strange call to have a trs midi port on a midi controller.
I wish to know more
I was about to buy Launchkey Mk4 37, gotta see reviews of this now. The M VAVE is pretty decent though
For this price it is a fantastic value. But depends on built quality and Midi configuration possibilities without using an external PC.
I play on my daily train commute with it and a pair of headphones, and the phone BT for DX7 patch editing. it’s light and small enough to fit in my backpack, and for the price it has no rivals.
Hi, I have my SMK-37 since thursday, and the synth is amazing! It does support BT audio, but only as an input (it acts as a BT speaker). It does make sense they didn’t try to implement BT audio output due to the latency of the L2DP profile, but I’d love to see them try with AptX-LL. Also, I’d love for this thing to have its own speakers (if it acts as a BT speaker, let it be one). So the only thing you can the BT audio use for is audio input for play-along. About BT MIDI, you can make it work on Windows using an app from m-vave’s website, but on Android I didn’t manage it to work properly in any but one app (“Piano MIDI BLE USB”). That’s a pitty, because when you are on the move, you can’t send to your phone neither a BT audio, nor a BT MIDI, and have to use the OTG cable anyway (which BTW works perfectly). As other fearure goes, the beat pads are small and not very responsive, the sliders are wobbly and plasticky and the keys are springy withou any feedback. Don’t take my word for it because it is actually my first MIDI keyboard and I have nothing to compare it to (other than my idea of a perfect keyboard), and it still has a great value for a 100 USD, but you can tell it is not a 300 USD keyboard…
An FM engine with 32 algorithms sounds like DEXED. There is probably a Raspberry Pi or some such in there.
no Raspy. Every on one PCB. Not sure how they did it.
Is there an ASIC or FPGA in there? I can’t think how they would duplicate a DX7 with discrete components for under £100.
On the Sequencer.de forum, they opened the unit and it’s a JieLi AC69xxxx controller and there is also a Audio/Bluetooth SoC with built-in audio DSP.
It’ll be an ARM microcontroller, so similar to the rpi’s core (or teensy or daisy and on and on) but without actually using one (like Korg insisted on doing for some reason). It’s definitely Dexed/MicroDexed and I think one of the reasons people run into odd glitches is because the factory patches are literally the DX7 factory patches and have some quirks that cause that in every hardware Dexed instance I’ve played with. Loaded mine up with some better or more modern patches and I haven’t had any of the weird patch glitches since.
They were probably designing this controller and realized that the ARM microcontroller they were going to use anyway (or one that cost a tiny bit more) had a ton of leftover processing power and some bright spark at M-VAVE suggested they throw in a synth. I’m hoping that means they’ll keep working on the firmware and add some more patch banks and more complete onboard editing.
If they are using the original DX7 patches I wonder if the glitches are related to how the first DX7 keyboard listed the velocity values to 100 or thereabouts, so a modern keybed outputting up to 127 could do some unexpected things.
Ugh, friggin autocorrect: “limited”, not “listed the velocity values.”
I already owned the SMK-25 but ordered this immediately after your other article alerted me to it. For my purposes it is almost perfect as it’s compact and the Bluetooth function eliminates the need for more cables in my tiny recording space. If it wouldn’t add much to the cost I would have loved a built in speaker as the synth is pretty decent but I can smell a little burger shaped speaker into the audio output or into my iPhone and it’s almost just as good.
it’s generally quite sturdy but being so cheap I have found that two of the faders can be easily lifted clean is so that’s worth bearing in mind. If I can afford something more upmarket it may still be worth it but for me it was a choice between this or no 3 octave Bluetooth midi keyboard at all.
I’d recommend this to anyone on a budget in heartbeat. Same as the SMK-25 It has limited usage with Ableton as a controller (as far as I know anyway) so I’m holding out hope someone will release a patch for that ASAP. It’s still a new release but fingers crossed that won’t be long.
Is there any information for how many hours the Midi keyboard can work in Bluetooth ?
I don’t have an exact number but for me it worked more than 4 hours without extra power