Multi-engine synthesizer with subtractive, FM, wavetable, and sampler engines. Ships as CLAP plugin, VST3 plugin, and standalone app with ImGui GUI. Pure C engine (C99/C11), real-time safe, cross-platform.
Latest Release — Windows installer/zip, Linux tar.gz/AppImage, macOS DMG/zip
- 4 synthesis engines — Subtractive (dual osc, sub, noise, unison), FM (4-op, 8 algorithms), Wavetable (4 banks + import), Sampler
- 7 filter types — LP, HP, BP, Notch, Ladder 24dB, Comb, Formant — dual filters with serial/parallel routing
- Modulation matrix — 8 slots, 16 sources (3 LFOs, envelopes, mod wheel, velocity, aftertouch, macros, MPE)
- 15 effects — Delay, Reverb, Chorus, Phaser, Flanger, Distortion, Bitcrusher, Compressor, and more
- Recording — WAV/FLAC/MP3 with timestamped filenames
- 70 factory presets — across bass, lead, pad, keys, FX categories
- 7 themes — Dark, Hacker, Midnight, Amber, Vaporwave, Neon, Light
- Real-time oscilloscope — pinned waveform display
- Arpeggiator — 5 modes, rate sync, gate control, 1-4 octave range
- MPE support — per-note pitch bend, pressure, slide
- 2x/4x oversampling — reduces aliasing in oscillators
See FEATURES.md for the complete feature list.
# Linux (requires SDL2)
sudo apt install libsdl2-dev
mkdir build && cd build && cmake .. && make -j$(nproc) && ctest
# Windows cross-compile (MinGW from WSL)
cmake -B build-win64 -DCMAKE_TOOLCHAIN_FILE=cmake/mingw-w64-gui.cmake
cmake --build build-win64 --target oxs_standalone oxs_clap oxs_vst3 -j$(nproc)| Format | Windows | macOS | Linux |
|---|---|---|---|
| CLAP | C:\Program Files\Common Files\CLAP\ |
~/Library/Audio/Plug-Ins/CLAP/ |
~/.clap/ |
| VST3 | C:\Program Files\Common Files\VST3\ |
~/Library/Audio/Plug-Ins/VST3/ |
~/.vst3/ |
synth_api.h (public API — opaque handle)
├── Atomic params (continuous knobs)
├── Command queue (note on/off, preset load)
├── Output events (peaks, voice activity)
└── Mod matrix (8 slots, per-voice evaluation)
Engine internals (private):
oscillator → filter → filter2 → envelope → 3x LFO → voice manager → effects → master
All consumers (ImGui GUI, CLAP/VST3 plugin, standalone) interact exclusively through synth_api.h. Thread-safe by design — atomic params, lock-free SPSC queues, zero allocations in audio path.
MIT License — see LICENSE