Awesome M-VAVE FM-1

A curated list of resources, tools, custom firmware and open source work around the M-VAVE (Cuvave) FM-1 pocket FM synthesizer.

The FM-1 is a battery-powered, six-operator FM synthesizer with 32 algorithms, 27 silicone keys, a colour TFT screen, built-in effects, an arpeggiator and a step sequencer. It speaks Yamaha DX7 SysEx, so decades of DX7 patches load straight into it. It is built around a JieLi AC791N (WL82) SoC and updates its firmware over USB-MIDI SysEx, which is why it has become one of the most hackable synths of 2026: the updater was reverse-engineered within weeks of launch and a family of open source firmwares now runs on it.

Flashing unofficial firmware is at your own risk. The flash has a single bank and the board has no debug header, so read the recovery section below before you install anything.

Contents

• Official
• Custom firmware
  • Open source
  • Closed source
  • Not a synth
• Reverse engineering and firmware development
• Firmware update and recovery
• Editors, librarians and companion software
• Patches and sound banks
• Hardware add-ons
• Documentation and guides
• Articles and reviews
• Videos
• Communities
• Related M-VAVE projects

Official

• Product page - Specs and feature overview. Also at cuvave.com.
• Downloads - M-UPGRADE updater for Windows and macOS, the latest .fwsc firmware (V15, July 2026), MIDI control reference and release notes.
• Firmware V15 - Current official firmware image. Custom firmwares expect you to be on V15 first.
• MIDI control reference (EN) - Official CC map, effects on their own MIDI channel.
• Release notes - Official changelog for every firmware version.
• User manual (PDF) - Multi-language printed manual. Also mirrored on manuals.plus.

Custom firmware

All of these install over USB from Chrome or Edge in a couple of minutes, and M-VAVE's own updater takes you back to stock. Most of the open source ones descend from Felucca.

Open source

• Felucca - Multi-engine synth firmware by Leo Kuroshita (Hügelton Instruments). Thirteen engines (6-op FM, VA, phase distortion, chiptune, sampler, granular, physical modelling, organ, drums), four tracks, 64-step sequencer, song mode, mod matrix, USB audio, web installer and web editor. The platform most other firmwares build on. GPL-3.0.
• SLOOP - Live four-track groovebox by 3dSam: three synths plus a drum machine, 37 drum kits, punch-in FX, layer system, song mode, web editor. Based on Felucca. GPL-3.0.
• X0X - ReBirth-style groovebox by Charles Vestal: TR-909, TR-808, two TB-303s with TB-3PO acid generators and a breakbeat slicer, each with its own sequencer. Has a browser emulator and manual. Felucca fork. GPL-3.0.
• Jangada - Felucca fork adding superwave analog, a modulation matrix, latched drones, ratchets and synthesized drum kits. GPL-3.0.
• Melodee - Felucca derivative that went its own way: ten engines, eight patterns per track, STUDIO workspaces, four-channel USB audio input, TR-808 kit. Web installer. GPL-3.0.
• SLOOP ALG - Experimental SLOOP fork (Chinese README) adding DX7, VA, Karplus-Strong, pluck and additive engines, with its own web installer and editor.
• FM-1 B-Boy Edition - Early-stage sampler/groovebox firmware that treats the FM-1 as a late-90s chop sampler with three sample tracks and an FM lane.
• Lunar Modulator - Research-stage open firmware built on Mutable Instruments engines (Plaits, Braids, Rings) and a Movy-style sequencer. Nothing flashed yet, but the virtual FM-1 in the browser is playable and the docs are a good map of the whole reverse-engineering effort. MIT.
• fm1-polyseq - Polyphonic 16-step sequencer and hardware abstraction layer in strict C99, written from scratch for the pi32v2 CPU.

Closed source

• FM-1+VA - The first third-party firmware, by Madeline (Baud Girl). Keeps the stock FM engine, adds a virtual analog engine with supersaw, a 64-step dot-matrix sequencer with ratchets and chance, four assignable knobs on every screen, and a cleaner menu. Free, with a manual and web installer. The author has said the source will be released.
• Groove OS - Commercial eight-track groovebox firmware by Peter Gombos ($29). FM and VA engines, up to 20 voices, per-track loop lengths, drum machine, performance mode, browser emulator and manual. Built on top of the V15 firmware.

Not a synth

• fm1-nes - NES emulator running on the FM-1, published as a worked example of custom firmware development with board-support code and USB serial diagnostics. Apache-2.0.
• fm1-doom - Doom engine port for the FM-1, in progress.

Reverse engineering and firmware development

• FM-1-RE - The deepest public analysis of the stock firmware: architecture, memory map, OTA protocol captures, security audit of recovery entry points, Ghidra scripts and V13/V14 firmware images. WTFPL.
• fm1-custom-fw - Teardown photos, hardware notes (chip, flash, no debug pads), analysis of the macOS M-UPGRADE app and a Python SysEx flasher and scanner.
• fm1-nes GETTING_STARTED - Source-only integration with the JieLi AC79/WL82 SDK, build setup for the pi32v2 toolchain, and guides on application-only updates that preserve the bootloader. Start here if you want to write your own firmware.
• fm1-emulator - Rust emulator that runs FM-1 firmware images (.fwsc, .elf, .bin) on your desktop with the screen, buttons and USB serial console, so you can test without flashing. GPL-3.0.
• fm1-firmware-patcher - Binary patches for the stock V15 firmware: Dexed-accurate detune, removes aftertouch vibrato, recolours the oscilloscope. Unlicense.
• MVAVE-M-UPGRADE-decompiled - Decompilation of the official updater application.
• jielie - Reference site for JieLi SoCs, the family the FM-1's AC791N belongs to.
• jl-uboot-tool - JieLi flasher and dumper. Source of the wl82loader.bin used by FM-1 Transporter.
• ghidra-jieli - Ghidra processor module for JieLi's pi32v2 CPU, needed to disassemble the firmware.
• jl-misctools - Miscellaneous JieLi utilities.
• Schwung - Charles Vestal's framework for the Ableton Move. Not an FM-1 project, but X0X and Lunar Modulator borrow its 909, 808, 303 and PSX Verb modules.

Firmware update and recovery

Stock updates and every custom installer go over USB-MIDI SysEx. If a flash fails the device may not boot, and the only way back in without opening the case is the chip's mask-ROM USB download mode, which needs a small hardware dongle.

• fm1-linux-update - Update stock V14 to V15 from Linux with verification, since M-VAVE only ships Windows and macOS updaters. MIT.
• fm1_flasher.py - Standalone CLI flasher and preset uploader from the fm1-custom-fw project.
• fm1_ota.py - Linux USB-MIDI update client from the FM-1-RE project, with offline protocol tests.
• FM-1 Transporter - Read and write the FM-1's flash from a Mac through a Seeed XIAO RP2040 wired to the USB data lines. Dumps the full flash in seconds and is the recovery path for a device that no longer starts. MIT.
• USB_KEY dongle notes - Lunar Modulator's write-up of the RP2040 dongle that forces the AC791N into download mode over USB-C.
• How to update the firmware - Plain walkthrough of the official M-UPGRADE process.
• fwradar changelog - Version history with changelogs for V09 through V15.

Editors, librarians and companion software

• FM1 Editor & Librarian - Browser-based DX7 voice editor and patch librarian built for the FM-1 by Benny Sparra: ten local banks, full operator editing, the FM-1 effects chain, SysEx import/export, six languages. Works with stock and FM-1+VA firmware. Source, MIT.
• DXcompanion - Free browser editor for the whole Yamaha DX family, with beta FM-1 support.
• Dexed - The open source DX7 emulator and editor. The FM-1 accepts single-parameter SysEx from it, so you can edit live from the plugin.
• FM-1 Workbench - Web app, Android app, VST3/CLAP controller plugin and an MCP server for the FM-1, with a DX7 voice library, randomize/mutate, drum sequencer and MIDI file player. Live. GPL-3.0.
• Virtual FM-1 - Software FM-1 as a standalone app and VST3/AU plugin for macOS, Windows and Linux, with two-way preset and pattern sync to hardware running FM-1+VA. GPL-3.0.
• FM-1 Pulses - Generative browser sequencer that broadcasts MIDI live and can freeze 64-step phrases into the FM-1's patterns on FM-1+VA firmware. Live.
• FM-1 Utility - Dependency-light Web MIDI editor for the FM-1.
• fm1-read-voice - Read the current voice back from the FM-1 over USB MIDI, which the stock firmware does not offer through other editors.
• fm1-bank-sender - Android APK to send .syx sound banks to the FM-1 from a phone.
• fm1_soundbank_app - Command-line tool to list, reorder and send a 128-preset soundbank over USB MIDI.

Patches and sound banks

• fm1-factory-presets - The original 128 factory voices recovered as four DX7 bank dumps, since the onboard reset only restores imported data. Includes SysEx protocol notes, a provenance table tracing 126 voices to known DX7 libraries, and an FM synthesis tutorial PDF. CC BY-SA 4.0.
• fm1-banks - 26 thematic 32-voice DX7 banks (832 patches) with provenance tracking and an audio gallery.
• This DX7 Cartridge Does Not Exist - Neural-network-generated DX7 cartridges, fresh every reload. Loads straight into the FM-1. Source.
• Ambient & Dreams - Commercial soundbank by NatLife Sounds made for the FM-1.

Hardware add-ons

• fm1-sustain-footswitch - Arduino board that turns a 3.5 mm sustain pedal into MIDI CC64 on the FM-1's TRS MIDI in, with schematics.
• FM-1 Bonus Box - ESP32-S3 companion box: sustain pedal, rotary preset browser with a round TFT, WiFi soundbank manager, USB MIDI keyboard host and a sing-on-key trainer.

Documentation and guides

• FM-1 MIDI Guide - Baud Girl's readable MIDI implementation: channels, CC map for the six effects, SysEx, clock sync.
• fm1-guide - Practical notes: sequencer tutorial, the V15 reverb fix and updating from Linux.
• FM-1 on Tao of Mac - Rui Carmo's running notes and link collection on the device.
• FM-1 SysEx protocol - Handshake, bank transfer and 7-bit payload encoding, documented while recovering the factory banks.
• OTA protocol and architecture docs - USB-MIDI framing, session behaviour and memory layout from the FM-1-RE project.
• Felucca BUILDING.md - How to build a Felucca-family firmware from source.
• fm1-nes APP_UPDATES - How application-only updates preserve the stock bootloader.

Articles and reviews

• M-VAVE FM-1 review - Synth Anatomy's full review.
• FM-1 V15 update - Launch coverage and the V15 feature rundown.
• Patch librarian - On Benny Sparra's browser librarian.
• Baud Girl FM-1+VA - The first custom firmware.
• Felucca - Coverage of the 1.0 release.
• SLOOP - On the four-track groovebox firmware.
• X0X - On the ReBirth-style firmware.
• Groove OS - On the commercial eight-track firmware.
• Custom firmware collection - Piano & Synth Magazine's comparison table of the firmwares.
• Free custom firmware for Mvave FM-1 - Sonicstate on FM-1+VA.
• MatrixSynth: Felucca, FM-1+VA, Groove OS - Video round-ups.
• Time To House - Launch article.
• Noizefield: SLOOP - SLOOP coverage.

Videos

• M-Vave FM-1 Review - The $70 Pocket DX-7 - Synth Anatomy's video review.
• Maks Makes: MIDI CC mappings - Working out the effect CC numbers before M-VAVE published them.
• Sound import tutorial - Loading DX7 banks over SysEx.
• Firmware V09 upgrade tutorial - Official-style walkthrough of the updater.
• Use the FM-1 as a Bluetooth MIDI controller - Driving an iOS synth over BLE MIDI.
• Can the FM-1 make a full song? - No-talking demo track from factory presets.
• FM-1+VA full tutorial - NatLife Sounds on the VA engine and new sequencer.
• Felucca 0.9 full guide - Walkthrough and sound demo.
• Felucca first look - Multi-sequencer, engines and scale mode.
• Felucca jam session - Live performance on Felucca.

Communities

• KVR Audio thread - Long-running thread where the factory preset recovery and much of the early tooling were first shared.
• Elektronauts thread - Workflow discussion and firmware news.
• Gearspace thread - Owners' thread.
• Plugg Supply - Forum post and discussion on the browser patch librarian.
• GitHub topic: m-vave - Repositories tagged with the brand.

Related M-VAVE projects

Not about the FM-1, but the same company, often the same chips and the same reverse-engineering crowd.

• smk37-firmware-custom-mod - Custom firmware and flasher for the SMK-37 Pro keyboard, which shares the FM-1's DX7 engine.
• smk-37-pro-docs - Community documentation for the SMK-37 Pro.
• mvave-chocolate-sysex and OpenChocolate - SysEx protocol and open web configurator for the Chocolate footswitches.
• mvave-blackbox-reverse-engineering and mvave-blackbox-edit - Protocol research and a Web Bluetooth editor for the BlackBox amp modeller.
• Cuvave Looper Pro protocol - SysEx protocol notes for the Looper Pro.

Contributing

Contributions welcome. Read the contribution guidelines first.