Synthesis

rancorSynth

rancorSynth is a free software synthesizer developed by Rancorsoft. Available format(s): VST for Windows.

rancorSynth is a free software synthesizer that offers a streamlined interface for quick sound synthesis. It combines the most common modules many expert sound designers use in a very compact manner. This allows you to have many instances of the synth on the screen at one time and quickly adjust parameters, or layer many sounds together in an efficient way.

rancorSynth also has a unique “Rand” button which quickly randomizes all parameters. Lacking inspiration or ideas? Let the synth conjure up a sound for you! You can then use that sound as a starting point, or hit “Rand” again until you find something you like a bit better.

Here is a full feature list:

2 Oscillators – Sin, Square, Saw or Noise wave.

1 LFO with toggle button.

Filter module.

Master volume control.

Lightning fast randomization of all parameters.

Preset loading, saving, renaming.

All controls fully MIDI mappable and can be automated by DAW software (like Ableton Live!).

52 great Free Presets.

Check out the demo video @ {See video at top of page} :).

http://rancorsoft.com

Rainbow

Rainbow is a free software synthesizer developed by BigTick. Available format(s): VST for Windows.

VSTi & Standalone versions.

FM, AM, additive and subtractive synthesis.

1 to 4 oscillators per voice.

Up to 24 voices (CPU dependant).

Selectable shape (sine, saw, square, triangle, noise).

Coarse / Fine tuning knobs, with selectable keyboard tracking mode.

LFO mode.

Distortion (Waveshaping knob).

APDSR (Attack/Peak/ Decay/ Sustain/ Release) level envelope.

Control of the level by MIDI velocity and/or key position.

4×4 Frequency and Amplitude modulation matrix.

Selectable Low, High, or Band pass double mode filter, with cutoff and resonance controls.

APDSR envelope and env mod knob.

Resonance controllable by MIDI velocity.

APDSR pitch envelope.

Portamento.

High-quality oversampling mode with antialias filter.

Fully midi-controlled, all controllers can be customised.

Supports Doepfer Pocket Dial controller.

16 step sequencer.

Microtuning support.

http://www.bigtickaudio.com/

Ragnarök

Ragnarök is a free software synthesizer developed by Full Bucket Music. Available format(s): VST, Audio Unit for Windows, macOS.

Ragnarök is a software instrument for Microsoft Windows (VST) and macOS (VST/AU) simulating a custom-built one-of-a-kind analog synthesizer from 1980. It is written in native C++ code for high performance and low CPU consumption.

Ragnarök is the collaborative work of Hans Peter aka CrimsonWarlock aka TechnoGremlin (synth concept, GUI design, user manual, patch programming) and Björn aka Full Bucket (DSP+GUI+patch programming). Read more about the background of this project in the user manual and in the respective KVR thread.

The main features of Ragnarök are:

Up to 64 voices polyphony including portamento.

Unique 3+1 band-limited oscillator bank – up to four oscillators per voice.

Additional white noise generator.

Multi-pole filter (6–12–18–24 dB/Oct low-pass or high-pass) with resonance.

Two envelopes (ADSR or AD) with exponential slopes.

Low frequency oscillator.

Built-in Overdrive effect and 7 band graphic equalizer.

Cool repeat/pseudo arpeggiator functionality.

Double precision audio processing.

All parameters can be controlled by MIDI controllers.

Exchangeable graphics (for individual skinning).

Plug-in supports Windows and macOS (32-bit and 64-bit).

Here is Hans Peter’s KVR OSC submission featuring Ragnarök:

https://soundcloud.com/gridlock-momentum/crimsonwarlock-midsummernight

http://www.fullbucket.de/music/vst.html

Radio

Radio is a free software synthesizer developed by Softrave. Available format(s): VST for Windows.

This synth produces radio noises synced to host tempo.

http://www.tikov.com/softrave/softrave.htm

Rack

Rack is a free software synthesizer developed by VCV. Available format(s): for Windows, macOS.

VCV Rack is the engine powering VCV modules. Add modules, connect cables, edit parameters, and save/load patches. Create generative patches with your mouse, perform with your MIDI keyboard controller, or connect it to your favorite DAW using the VCV Bridge VST/AU plugin (coming soon).

In Rack, control voltages and audio signals are equivalent, so you can modulate parameters with sonic-range VCOs to create customizable FM synths or chaotic wave-shaping oscillators. If you already own a modular synthesizer, you can enhance your setup with an audio interface or a CV-MIDI-CV interface module with Rack’s CV Interface (coming soon).

Find out more at vcvrack.com.

https://vcvrack.com/

RA Mowg

RA Mowg is a free software synthesizer developed by Roberson Audio Synthesizers. Available format(s): VST for Windows.

RA Mowg is an emulation of a Moog Minimoog Model D. Another addition to the line-up of Roberson Audio’s collection of vintage replica synths, many many months have been spent to create an instrument that not only resembles the Minimoog in appearance, but delivers the same feel while playing. From the deep, full-bodied filters, to the mellow analog-style oscillators, to the distortive drive from feedback-looping the output, this instrument can give you the feeling of playing a Minimoog without spending a small fortune to do so. For more technical info and notes before playing the synth, see the ReadMe file.

http://www.robersonaudio.com

R2

R2 free software-synthesizer by KlangLabs

R2 is a free software synthesizer developed by KlangLabs. Available format(s): VST for Windows 64b.

R2 is a hybrid synth and effect processor, just assign a MIDI track to it to play notes and use an external source (preferably voice) to make the pitch change. You can achieve interesting sounds with this plug, besides the famous Star Wars R2-D2 blips you can use it as a synth and use your voice to make weird vibratos.

https://www.kvraudio.com/developer/klanglabs

QuirQuiQ

QuirQuiQ is a free drum machine VST plugin developed by Ocean Swift Synthesis. Compatible OS(s): Windows.

QuirQuiQ (Pronounced: “Quirk Kick”) is Punchy kick synth that fits in your shuttlecraft or in your pocket with a big sound and tiny CPU footprint. Utilizes digital envelopes allowing for precise control, and presented in a clear, resizable vector interface.

Slam the dancefloor with sharp and pounding kicks, ooomph away with long breathy thumps, go for a grungy and snappy sound or find just that right balance that is perfect for your track.

http://www.oceanswift.net

Quatrix

Quatrix is a free software synthesizer developed by Jeff51. Available format(s): VST for Windows.

As the name may imply, everything on Quatrix is in quadruplicate.

4 VCOs with individual EG pitch.

4 VCFs with individual EG.

4 VCAs with individual EG.

4 LFOs, 4 modulations and 1 supplementary EG.

Possibility of FM and Function “Synchro” between the 4 VCOs.

Flanger.

High CPU consumption.

http://perso.wanadoo.fr/MAOpassion/

Quark

Quark is a free software synthesizer developed by TorQue Audio. Available format(s): VST for Windows.

Quark is based on the Muon Atom Pro but is not an emulation. It’s suitable for synthetic basses.

http://sarvst.110mb.com/