MJSFX is a free, native macOS sounds and effects design studio.
Start from a generator (lasers, explosions, blips, hits, etc) then build with layered oscillators, each with its own pitch sweep, envelope, and filters. Chain reverb, delay, distortion, bitcrush, and more per layer or across the whole sound, plus LFOs that can modulate knobs, including other LFOs. Everything exports to WAV, including retro formats like 22kHz/8-bit and per-layer stems. Sounds are JSON files as are all configuration files.
It has extensive MIDI hardware support with soft pickup and per-controller profiles, a built-in library with folders and filtering, workspaces, a live "Sound Portrait" visualization drawn from real engine output, and twenty themes plus a browser-based theme builder. No in-app AI, but the direct download (and homebrew) version ships with an MCP server. Docs on the site.
No ads, no telemetry, and you own everything you make. Requires Apple Silicon and macOS 14+.


