# X0X: turn a small synth into a full groovebox

909 and 808 drums, dual acid basslines, breakbeat playback and song sequencing on the original device.

## Hardware
M-VAVE FM-1

The synth’s buttons and audio output become a drum machine and sequencer.

## Shopping list

Parts for one build. Reuse equipment you already own. Quantities are planning quantities unless the creator explicitly specifies a count; kit contents are not additional purchases.

Quantities are for one build. Unless marked source-specified, they are planning quantities; confirm kit contents and the chosen configuration before ordering.

### Confirm before buying
- Confirm the installed flash chip and the chosen firmware release before purchase; newer UC25HQ80 units may require beta support.
- Thai retailer identified; international shipping and the supplied hardware revision remain unverified.

### 1 × M-VAVE FM-1
- Requirement: Required
- Quantity basis: Planning quantity for one build; check the selected configuration
- Purpose: Firmware target.
- Notes: Check the selected seller variant and flash revision. New UC25HQ80 units are not equivalent to a tested older unit. Music Arms lists the actual FM-1; shipping outside Thailand and flash revision must be confirmed. A seller page does not verify third-party firmware compatibility.
- Destination: https://www.musicarms.net/m-vave-fm-1/
- Match: Exact model; Thai retailer, hardware/flash revision not guaranteed
- Link review: Page checked; stock not assessed
- Evidence: Creator source
- Source: https://www.theverge.com/gadgets/1013493/vibe-coding-ai-music-gear-hacking-custom-firmware
- Source: https://github.com/charlesvestal/fm1-x0x
- Source: https://www.musicarms.net/m-vave-fm-1/

### 1 × USB-C data cable
- Requirement: Required
- Quantity basis: Planning quantity for one build; check the selected configuration
- Purpose: Connect to the computer for programming or data.
- Notes: A charge-only cable cannot flash firmware. Example requires a USB-A host port. If your computer has only USB-C, use an appropriate USB-C data cable instead. Reuse the device’s included cable where possible; this is not a standalone power-supply recommendation.
- Destination: https://www.adafruit.com/product/4474
- Match: Accessory example: USB-A to USB-C, 1 m, data capable
- Link review: Page checked; stock not assessed
- Evidence: Setup requirement — check against your configuration
- Source: https://www.theverge.com/gadgets/1013493/vibe-coding-ai-music-gear-hacking-custom-firmware
- Source: https://github.com/charlesvestal/fm1-x0x
- Source: https://www.adafruit.com/product/4474

### 1 × Computer with Chrome or Edge
- Requirement: Tool
- Quantity basis: Planning quantity for one build; check the selected configuration
- Purpose: Build, configure or flash the software.
- Sourcing: Use existing equipment or match the specification above. No exact purchase link verified.
- Evidence: Setup requirement — check against your configuration
- Source: https://www.theverge.com/gadgets/1013493/vibe-coding-ai-music-gear-hacking-custom-firmware
- Source: https://github.com/charlesvestal/fm1-x0x

### 1 × Headphones / speakers or USB audio host
- Requirement: Optional
- Quantity basis: Planning quantity for one build; check the selected configuration
- Purpose: Monitor the synthesizer output.
- Notes: FM-1 already has an onboard speaker. External headphones, speakers or USB audio are optional monitoring routes; confirm the selected custom firmware supports the route.
- Sourcing: Use existing equipment or match the specification above. No exact purchase link verified.
- Evidence: Setup requirement — check against your configuration
- Source: https://www.theverge.com/gadgets/1013493/vibe-coding-ai-music-gear-hacking-custom-firmware
- Source: https://github.com/charlesvestal/fm1-x0x
- Source: https://www.musicarms.net/m-vave-fm-1/

### 1 × MIDI keyboard / controller
- Requirement: Optional
- Quantity basis: Planning quantity for one build; check the selected configuration
- Purpose: Play external MIDI notes.
- Notes: Not needed for all sequencing modes; choose a compatible MIDI connection.
- Sourcing: No exact purchase link verified; confirm the model and requirements above before ordering.
- Evidence: Creator source
- Source: https://www.theverge.com/gadgets/1013493/vibe-coding-ai-music-gear-hacking-custom-firmware
- Source: https://github.com/charlesvestal/fm1-x0x

Source reviewed, not assembled or hands-on tested. A working product page does not confirm stock, firmware compatibility or a complete build.

## Setup
Unofficial firmware

## Coding tool
Claude / AI coding agents

## How the agent helped
The Verge specifically lists X0X among firmwares with Claude attribution or explicit AI disclosures; repository explains the instrument and testing setup.

## Before you build
Beta replacement firmware. Busy patterns can reduce audio quality; save a recovery path before flashing.

## Sources
- Original build: https://www.theverge.com/gadgets/1013493/vibe-coding-ai-music-gear-hacking-custom-firmware
- Supporting source: https://github.com/charlesvestal/fm1-x0x

Source reviewed 2026-11-04. Not hands-on tested.