# M-VAVE FM-1 Open: the green light for custom firmware and community hacks > Source: > Published: 2026-10-19 00:03:28+00:00 **With the FM-1 Open, M-VAVE welcomes developers creating alternative firmware and offers them a dedicated space to bring their ideas to life.** The little FM-1 Synthesizer is very much in vogue—and has been since summer, with interest surging further over the past few weeks thanks to an almost daily-growing range of alternative firmwares. What does M-VAVE think? Now we know: the Chinese company welcomes it, and with FM-1 Open, M-VAVE has launched an open development project where you can manage the technical and firmware aspects. ### M-VAVE FM-1 Open At the start of summer, the developers released the FM-1, a small, portable, battery-powered FM synthesizer. I [reviewed](https://synthanatomy.com/2026/07/m-vave-fm-1-a-budget-friendly-dx-7-style-desktop-fm-polysynth.html) it at the time. Later, people discovered a “backdoor” and used AI to create custom firmware, which further sparked interest in the device. The little FM synth is now a full-fledged groovebox à la ReBirth, an Oberheim-style polysynth, or even an Omnichord-inspired instrument. M-VAVE welcomes this lively development so much that they have now opened up the synth’s backend with the FM-1 Open. It’s the official firmware and development project for FM-1 users and developers. It features an English/Chinese browser workbench where you can explore the instruments, edit device projects, manage samples, or flash firmware. More importantly, it includes application source code and a companion SDK available on GitHub. Developers can use the source and SDK to study and extend its features and build their own FM-1 applications. You can also explore the main music-making features in your browser without connecting a device. According to M-VAVE, the application source uses GPLv3 with an SDK linking exception. The proprietary underlying engine is supplied as a binary SDK. SDK and third-party components retain their respective terms ### Alternative M-VAVE Firmware If you’d rather make music than build your own firmware, M-VAVE offers a second official firmware that is part of the new FM-1 Open development project. It combines the usual suspects of the recent custom firmwares: **6-operator FM synth, 303-style bassline synth, 808-style drum machine, chiptune synth, pluck synth**, and a **sample** r with eight shared sample slots. Independent tracks let you arrange melodies, bass, drums, and custom samples, edit their sounds and rhythms, and create looping patterns. Looking at the content, one notices many parallels to other engines. It seems M-VAVE has borrowed from other firmwares, though they don’t disclose this, which is a pity. They did the same thing with the Dexed project for the FM-1, which is also unfortunate. ### Makes sense! In recent weeks, hardware units based on digital code have been hacked, expanded, and rewritten at an intense pace. M-VAVE’s move with the FM-1 makes perfect sense and fits seamlessly with the spirit of the times. More hardware developers should take this approach as an example. I suspect that continuing to wall everything off, as we have for the past 20 years, is the wrong approach. Sooner or later, AI will make its way everywhere. Create SDKs or an open backend so people can build new things. This helps ensure existing hardware keeps improving and stays maintained, even if the original developer works on it only occasionally or no longer at all. M-VAVE FM-1 Open is now available for free in your browser, including the alternative official firmware and the Browser Workbench. **More information here: [M-VAVE](https://open.m-vave.com/fm1-workbench)**