OctaSine Free Open-Source FM Synth

OctaSine Free Open-Source FM Synth

OctaSine is a free and open-source frequency modulation-based synthesizer plugin that runs on macOS, Windows, and Linux.

Features

  • Four FM operators with parameters for volume, panning, modulation index, feedback, frequency modifiers (ratio, free and fine), envelope values (attack, decay, release) and toggling of white noise mode.
  • Flexible routing allows setting the operator modulation target (with some limitations) as well as the percentage of signal that is simply added to the final output, enabling additive synthesis.
  • Four LFOs with multiple waveforms, oneshot and loop modes and optional DAW BPM sync. They can target most operator parameters and most parameters of lower-index LFOs.
  • ADSR envelopes – each operator is connected to an attack-decay-sustain-release volume envelope with logarithmic slopes.
  • Per-operator white noise mode makes it easy to create percussive sounds such as hi-hats and cymbals.

OctaSine runs on macOS, Windows 10, and Linux in VST2-compatible DAWs. Synthesis is SIMD-accelerated where possible.

Supported platforms & download

Windows | macOS
VST

OctaSine

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