Feature Request: Headless MAME Synthesizer as a Linux Service for MIDI-to-Audio Processing

[senseab]

Hi MAME developers and community,

I’d like to propose a new feature for MAME that could greatly benefit users interested in retro sound synthesis and MIDI integration. The idea is to enable MAME’s synthesizer component to run as a headless Linux background service (e.g., a systemd service), capable of receiving MIDI input signals and outputting synthesized audio without requiring a graphical interface.

Why this matters

MAME’s accurate emulation of vintage sound chips (YM2612, SID, OPL, etc.) makes it a unique tool for retro music production. However, currently using MAME for MIDI-driven audio synthesis requires launching the full emulator with a visible window, which is impractical for headless setups, automation, or integration into MIDI workflows.

Proposed Functionality

1. Headless Mode:

   • Run MAME’s synthesizer core as a standalone Linux service (no GUI dependencies).
   • Configure via config files or CLI arguments (e.g., target sound chip, sample rate, audio backend).

2. MIDI Input Support:

   • Accept MIDI messages via ALSA/Jack MIDI or virtual MIDI ports (e.g., /dev/midi*).
   • Map MIDI channels/controls to emulated sound chip parameters (e.g., FM operator settings).

3. Audio Output:

   • Stream synthesized audio to PulseAudio, PipeWire, or directly to ALSA.
   • Optionally save output to a file (WAV/FLAC).

4. Service Integration:

   • Provide systemd/init scripts for easy management.
   • Allow control via D-Bus or UNIX sockets (start/stop, reload configs).

Use Cases

• Retro chiptune production pipelines using modern DAWs (e.g., Ardour, Renoise).
• Live performances with hardware MIDI controllers driving vintage synth emulation.
• Automated testing/benchmarking of MIDI-to-audio workflows.

Technical Considerations

• Reuse MAME’s existing sound core but decouple it from the emulator’s main loop.
• Leverage Linux’s low-latency audio/MIDI stack (e.g., JACK, rtkit).
• Minimal resource usage for Raspberry Pi/embedded device compatibility.

Community Benefits

This would position MAME as not just an emulator, but a flexible tool for preserving and interacting with retro sound technology in modern contexts. Similar projects (e.g., Timidity++ for software MIDI) exist, but MAME’s accuracy and breadth of supported chips are unmatched.

I’d love to hear thoughts from the community:

• Are there existing workarounds or forks that already enable this?
• Would developers/maintainers support such a feature?
• Could this be implemented as a plugin or separate binary to keep core MAME lightweight?

Thanks for considering this idea! Let’s discuss how to make it happen.