FM8

You can control the Native Instruments FM8 synthesizer from an MCP client by routing MIDI CC messages through a virtual MIDI port. This setup lets you dial in sounds and automate FM8 parameters from Claude Desktop, AnythingLLM, or other MCP clients, turning your FM8 into a programmable instrument under external control.

How to use

Use an MCP client to send MIDI CC messages to FM8 via the virtual port you create. You can map operator matrices, outputs, and frequency ratios to CCs and then instruct your MCP client to adjust those controls through natural prompts. Typical workflows include crafting a new FM8 patch by scripting operator modulations, routing operator outputs to desired levels, and tweaking harmonic relationships on the fly. For best results, ensure the FM8 MIDI input is wired to your virtual port and that your MCP client’s channel matches the port you configured.

How to install

Prerequisites you need before you begin: Node.js 18+, Native Instruments FM8, and a virtual MIDI port utility.

Step 1: Prepare the project

• Clone the MCP server repository
• Install dependencies
• Build the project

How to install

git clone https://github.com/thesigma1receptor/fm8MCP.git
cd fm8MCP
npm install
npm run build

FM8 setup on your system

Create and configure the virtual MIDI port, then direct FM8 to listen on that port. Use the steps below for Windows or macOS.

FM8 setup on Windows

1. Install and run loopMIDI
2. Remove any existing ports
3. Create port named `fm8

FM8 setup on macOS

1. Open Audio MIDI Setup
2. Window → Show MIDI Studio
3. Double-click IAC Driver
4. Enable "Device is online"
5. Create port named `fm8

Configure FM8

In FM8, set the MIDI input to the port named fm8. Then load the included MCP.f8c file from the Master tab and enable any operators that are off.

Claude Desktop Setup

Tell Claude Desktop how to run the MCP server locally. Use a stdio transport connected to the fm8 MIDI port and select channel 1.

Claude Desktop config example

{
  "mcpServers": {
    "fm8": {
      "command": "node",
      "args": [
        "C:/path/to/fm8-mcp-server/dist/server.js",
        "--transport=stdio",
        "--midi-port-name=fm8",
        "--channel=1"
      ]
    }
  }
}

AnythingLLM Setup

If you use AnythingLLM, you can enable the FM8 MCP server in your workspace and point it at the local server. The following configuration shows the structure you would add to the storage file.

AnythingLLM config example

{
  "fm8": {
    "name": "FM8 Control",
    "command": "node C:/path/to/fm8-mcp-server/dist/server.js",
    "args": ["--transport=stdio", "--midi-port-name=fm8", "--channel=1"],
    "env": {},
    "cwd": "C:/path/to/fm8-mcp-server"
  }
}

What you can control in FM8

FM8 Matrix (CC 0-62): all operator-to-operator modulation routes. Operator Outputs (CC 63-70): operator-to-output levels. Frequency Ratios (CC 72-77): harmonic/inharmonic relationships for each operator. See the included mappings for the complete CC reference.

Example prompts you can use

• "Create an FM bell sound"\n- "Set operator A to modulate B at 75%"\n- "Make a pure sine wave"\n- "Route operator C to output at full volume"\n- "Show all available FM8 controls"