Open Source Audio Plugins & Apps

A list of open source VST (and other format) plugin/app projects. The intention of this list is to catalog open source plugins or apps which are fully featured or are useful examples which have non-trivial features.

The main benefit of having Open Source plugins/apps is that the code itself is preserved for the future, so when the author(s) stop updating it the community can continue using and developing the software. Open Source projects are also a great way to learn how different audio FX/instruments are created.

https://openaudio.webprofusion.com

Please contribute links!

Audio Plugins

Plugin	Description	Type	Framework
ADLplug	FM Chip Synthesizer — OPL & OPN	Instrument	JUCE
andes	Sound synthesiser plugin based on Perlin noise	Instrument	JUCE
Airwindows	Various small and experimental effect plugins	Effect
amsynth	Analog-modelling (virtual analog) synthesizer	Instrument	GTK
Argotlunar	Real-time delay-line granulator	Effect	JUCE
Audio Effects	Plugins implemented from the explanations in the book “Audio Effects: Theory, Implementation and Application”	Effect	JUCE
BinAural VST	Mono-to-stereo plugin that positions sound in a 3D space using Head-Related Transfer Functions	Effect	JUCE
CHOW	A maximally truculent distortion effect	Effect	JUCE
Cloud Seed	Algorithmic reverb for emulating huge, endless spaces and modulated echoes	Effect
Cocoa Delay	Warm and lively delay	Effect	WDL-OL
Convolver	Impulse-response reverb	Effect	VSTGUI, JUCE
Dexed	DX7 FM plugin synth	Instrument	JUCE
Digits	Phase-distortion synth inspired by Casio CZ series	Instrument	VSTGUI
Distrho glBars	OpenGL bars visualization plugin (as seen in XMMS and XBMC/Kodi) adapted from jack_glbars	Effect	DPF
Distrho Juice Plugins		Misc	DPF
Distrho Kars	Simple karplus-strong plucked string synth based on the karplong DSSI example synth	Instrument	DPF
Distrho Mini-Series	Collection of small plugins based on LOSER-Dev Plugins	Effect	DPF
Distrho MVerb	DPF-based version of MVerb	Effect	DPF
Distrho ndc Plugs	DPF-based versions of some of ndc Plugs	Effect	DPF
Distrho Nekobi	Simple single-oscillator synth based on Roland TB-303	Instrument	DPF
Distrho ProM	Music-visualizer plugin based on projectM	Effect	DPF
Dragonfly Reverb	Hall-style reverb based on Freeverb3 algorithms	Effect	DPF
Element	Advanced Audio Plugin Host	Misc	JUCE
Eurorack	Diverse set of physical modeling sources, organic processors, wavetable oscillators, waveshapers, granular synths, and utility modules	Misc
Flutterbird	Simple pitch fluctuation	Effect	iPlug 2
Gverb/Gigaverb	Reverb	Effect	VSTGUI
Helm	Polyphonic synth with lots of modulation	Instrument	JUCE
hexter	Yamaha DX7 modeling FM synth for DSSI	Instrument	DPF
HiLoFilter	Simple hipass/lopass filter controlled with a single knob	Effect	JUCE
JuceOPLVSTi	FM synth based on Yamaha OPL2/3 emulation from DOSBox	Instrument	JUCE
Juno 6	Roland Juno 6/60 Synthesizer	Instrument
keithhearne/VSTPlugins	A collection of VST plugins	Effect	JUCE
K-Meter	Implementation of a K-System meter according to Bob Katz' specifications	Effect	JUCE
KickMaker	Synth specifically to create kick-drum sounds	Instrument	VSTGUI
LameVST	LameMP3 as an effect	Effect
Magical8bitPlug 2	Old 8bit game console style synth	Instrument	JUCE
mda	FX and virtual instruments for PC and Mac	Misc	(no GUI)
Mika Micro	Simple subtractive synth	Instrument	WDL-OL
MVerb	Studio-quality reverb using the Dattorro’s figure-of-eight reverb structure	Effect	VSTGUI
NotNotchFilter	Performance-oriented filter designed to replace the mid-EQ found in a standard 3-band DJ mixer	Effect	JUCE
ndc Plugs	VST plugins for Windows and OSX	Misc
OwlBass	Additive bass synth	Instrument	JUCE
OB-Xd	Based on the Oberheim OB-X	Instrument	JUCE
Oxe FM Synth	Multitimbral 8-operator FM synth (VST 2.4; Windows, Linux, macOS)	Instrument	VSTGUI
PulseDelay	Timed delay effect	Effect	(no GUI)
QtVST	VST plugins with a Qt interface	Effect	Qt
Regrader	Degenerative delay	Effect	VSTGUI
Roth-AIR	Mixing tool for easily adding airy, crispy presence to audio	Effect	JUCE
ScorchCrafter Guitar FX	Audio DSP FX and plugins, mostly for guitar (amp sim) and other FX	Effect	VSTGUI
ShoutVST	VST for streaming sound into Icecast/Shoutcast directly from VST hosts	Effect	VSTGUI, FLUID
Sound Analyser	Real-time audio analysis to allow anyone to quickly set up and experiment with different algorithms	Effect	JUCE
Surge	Subtractive wavetable synth	Instrument	VSTGUI
Synister	Subtractive synth	Instrument	JUCE
Syntage	VST 2.4 .Net Study Synth	Instrument
Temper	Digital distortion targeting VST, VST3, and AU for OS X and Windows	Effect	Faust, JUCE
Tunefish	VST virtual analog synthesizer	Instrument	JUCE
traKmeter	Loudness meter for correctly setting up tracking and mixing levels	Effect	JUCE
VCV Rack	Virtual modular synth	Misc	RtAudio
VSTSID	SID synthesizer instrument	Instrument
VST2413	FM synth based on emulator of YM2413 (OPLL) chip used in Sega Master System and FM-PAC MSX expansion	Instrument	(no GUI)
Wolf Shaper	Waveshaper plugin with spline-based graph editor	Effect	DPF
YK Chorus	Chorus audio effect plugin based on DSP code by TAL	Effect	DPF
zam-plugins	LADSPA/LV2/VST/JACK audio plugins for high-quality processing	Effect	DPF

Collections

• VCV library — a library of plugins compatible with VCV Plugin Manager
• Linux Synths - a list of linux based synths, some of which are open source

Open Source Audio Apps

Software	Source	Description
Ardour	Ardour/ardour	DAW
ASIO2WASAPI	levmin/ASIO2WASAPI	Universal ASIO driver for Windows
Audacity	audacity/audacity	Audio editor
Carla	falkTX/Carla	GNU/Linux Plugin Host
Element	Kushview/Element	Advanced Audio Plugin Host
FlexASIO	dechamps/FlexASIO	Universal ASIO driver for Windows
Giada	monocasual/giada	Loop machine
Guitarix	SourceForge → guitarix	GNU/Linux Virtual Amplifier
Helio Workstation	helio-fm/helio-workstation	Sequencer
HISE	christophhart/HISE	Cross-platform framework/application for building sample-based virtual instruments (VST, AU, AAX)
Hydrogen	hydrogen-music/hydrogen	Drum machine
NewMixer	jatinchowdhury18/NewMixer	Mixing Software
LMMS	LMMS/lmms	DAW
OpenMPT	OpenMPT/openmpt	Popular tracker (formerly ModPlug Tracker) for Windows with support for IT, XM, S3M, MOD modules, VST plugins and ASIO
OwlPlug	DropSnorz/OwlPlug	Audio plugin manager
orDrumbox	SourceForge → ordrumbox	Drum machine
Psycle	SourceForge → psycle	Modular music tracker
VCV Rack	VCVRack/Rack	Modular synth
Zrythm	zrythm/zrythm	DAW

Open Source Software Development Libraries

Library	Source	Description
Cabbage	rorywalsh/cabbage	Framework for developing audio plugins and standalone instruments with Csound
Csound	csound/csound	Programming language for sound and music synthesis
DPF	DISTRHO/DPF	C++ framework for creating cross-platform audio plugins
Faust	grame-cncm/faust	Functional programming language for real-time signal processing
FluidSynth	FluidSynth/fluidsynth	Real-time synth based on the SoundFont 2 specifications
iPlug 2	iPlug2/iPlug2	Simple-to-use C++ framework for developing cross-platform audio plugins/apps
JUCE	WeAreROLI/JUCE	Cross-platform C++ framework for developing desktop and mobile apps and audio plugins
jVSTwRapper	SourceForge → jvstwrapper	Wrapper to write audio plugins in Java (VST 2.4, AU, LADSPA; Windows, Linux, macOS)
libopenmpt	OpenMPT/openmpt	Cross-platform C/C++ module-playback library based on OpenMPT
PortAudio	Assembla → portaudio	Cross-platform audio I/O library
RtAudio	thestk/rtaudio	C++ classes for cross-platform real-time audio I/O
rust-vst	rust-dsp/rust-vst	VST 2.4 API implementation in the Rust language
Soundpipe	PaulBatchelor/Soundpipe	Lightweight music DSP library written in C; over 100 modules, many ported from Csound
VSTGUI	steinbergmedia/vstgui	User-interface toolkit mainly for audio plugins
WDL-OL	olilarkin/wdl-ol	Simple-to-use C++ framework for developing cross-platform audio plugins (superseded by iPlug 2)

Code Samples

• KlangFalter — a convolution audio plugin (e.g. for usage as convolution reverb)
• FFTConvolver — an audio convolution algorithm in C++ for real-time audio processing

Open Data Resources

• OpenAIR — the Open Acoustic Impulse Response Library (Convolution Reverb Impulse Responses to recreate reverb character of space and equipment/recordings)