All synths

Best open-source synthesizers

Open-source synths cannot be discontinued, license-locked or bought and shelved. Several of these are used on commercial records every day and rival paid plugins outright.

23 synths · updated 2026-09-11

  1. Vital by Matt Tytel: plugin interface screenshot
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    Vital

    Matt Tytel · Wavetable · VST3, VST2, AU, LV2, Standalone · Windows, macOS, Linux

    The wavetable synth that made Serum optional. Spectral warping, drag-and-drop modulation, all of it free.

    Download from vital.audioDetails

  3. Dexed by Digital Suburban: plugin interface screenshot
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    Dexed

    Digital Suburban · FM · VST3, AU, CLAP, LV2, Standalone · Windows, macOS, Linux

    The DX7 in your DAW. Loads original sysex patches, so forty years of FM sound design is yours for nothing.

    Download from asb2m10.github.ioDetails

  4. Odin 2 by TheWaveWarden: plugin interface screenshot
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    Odin 2

    TheWaveWarden · Virtual analog · VST3, AU, CLAP, LV2 · Windows, macOS, Linux

    A 24-voice analog-style synth with drawable waveforms and filters modelled on the Moog ladder and Korg 35.

    Download from thewavewarden.comDetails

  5. Cardinal by DISTRHO: plugin interface screenshot
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    Cardinal

    DISTRHO · Modular · VST3, VST2, AU, CLAP, LV2, Standalone · Windows, macOS, Linux

    VCV Rack as a plugin, with 1,382 modules baked in. Free, open source, runs in your DAW or in a browser.

    Download from cardinal.kx.studioDetails

  7. OB-Xf by Surge Synth Team: plugin interface screenshot
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    OB-Xf

    Surge Synth Team · Virtual analog · VST3, AU, CLAP, LV2, Standalone · Windows, macOS, Linux

    The Surge team’s open-source continuation of OB-Xd: Oberheim OB-X flavour, patch-compatible, GPL forever.

    Download from surge-synth-team.orgDetails

  8. RipplerX by Tilr (tiagolr): plugin interface screenshot
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    RipplerX

    Tilr (tiagolr) · Physical modelling · VST3, AU, LV2, Standalone · Windows, macOS, Linux

    Strings, beams, membranes, plates and tubes, coupled and struck. An open-source answer to Chromaphone.

    Download from github.comDetails

  9. Six Sines by BaconPaul: plugin interface screenshot
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    Six Sines

    BaconPaul · FM · VST3, AU, CLAP, Standalone · Windows, macOS, Linux

    Six sine operators that can all modulate each other at audio rate. Strange, deep and MIT-licensed.

    Download from github.comDetails

  10. Galdr by Sognevo: plugin interface screenshot
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    Galdr

    Sognevo · Virtual analog · VST3, AU, CLAP, Standalone · Windows, macOS, Linux

    2026’s new arrival: a black-metal-styled open-source synth with morphing wavetables and a granular Blizzard layer.

    Download from sognevo.comDetails

  11. Vaporizer2 by VAST Dynamics: plugin interface screenshot
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    Vaporizer2

    VAST Dynamics · Wavetable · VST2, VST3, AU, AAX, CLAP, LV2, Standalone · Windows, macOS, Linux

    A full commercial wavetable workstation, 220 mod destinations and all, handed to the world under GPL in 2023.

    Download from vast-dynamics.comDetails

  12. Helm by Matt Tytel: plugin interface screenshot
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    Helm

    Matt Tytel · Virtual analog · VST3, VST2, AU, LV2, Standalone · Windows, macOS, Linux

    Matt Tytel’s pre-Vital synth: 32 voices, formant filter, stutter effect. Archived in 2025 but still fantastic.

    Download from tytel.orgDetails

  15. OctaSine by Joakim Frostegård: plugin interface screenshot
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    OctaSine

    Joakim Frostegård · FM · VST2, CLAP · Windows, macOS, Linux

    A four-operator FM synth written in Rust, with a trick nobody else has: modulation panned across the stereo field.

    Download from octasine.comDetails

  23. amsynth by Nick Dowell: plugin interface screenshot
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    amsynth

    Nick Dowell · Virtual analog · VST2, AU, LV2, Standalone · Windows, macOS, Linux

    A classic two-oscillator subtractive synth developed since 2002, now with a JUCE interface and MTS-ESP tuning.

    Download from amsynth.github.ioDetails

More guides

Best free VST synths · Best free AU synths for Logic and GarageBand · Free synths with CLAP support · Best free synths for Linux · Best free synth apps for iPad and iPhone · Free FM synths · Free wavetable synths · Free virtual analog synths · Free modular synths