Free Software Synthesizers

FM-Four

FM-Four is a free software synthesizer developed by ToneBytes. Available format(s): VST for Windows.

FM-Four is a simple VST instrument that recreates four operators FM synthesis with some improvements like good known YAMAHA OPL/OPL2 chipsets. FM-Four can produce wide range of timbres that are rich in harmonics.

Main features:

8 FM Algorithms.

4 operators with coarse and fine tuning.

8 waveforms per operator (Sinus, Half-sinus, Abs-sinus, Quarter-sinus, Square, Triangle, Half-triangle, Abs-triangle).

Multimode LFO synced with BPM and with Random mode.

4 filters.

8 stage envelope generator for multimode modulator.

Distortion.

Internal chorus.

Internal 10 bands equalizer.

Easy control with pop-up menus.

64 factory presets.

Built-in preset manager with ability to patch name editing.

In addition, VST automation and full MIDI Learning are supported.

{See video at top of page}

http://tonebytes.com/

FireBird

FireBird is a free software synthesizer developed by Tone2 Audiosoftware. Available format(s): VST for Windows.

FireBird features what Tone2 claims is a “new, unique sounding synthesis” – Harmonic Content Morphing (HCM) – see below.

Features:

A new, unique sounding synthesis: Harmonic content morphing (HCM).

84 oscillator types containing 18,000 morphable waveforms.

38 different analogue modeled filter types.

True stereo mode, 4x unison mode, and up to 8 oscillators per voice.

Can sound like other synthesis methods – additive, subtractive, AM, FM, phase distortion, supersaw, vocoder, sync.

Can sound like natural instruments like piano, brass, organs…

23 spectral manipulations or “modifiers” can be applied to the oscillators.

IQM – intelligent micro tuning for cleaner chords.

Alias free oscillators, alias free FM, anti-aliased distortion, oversampling.

Sample accurate timing.

Digital precision as well as analogue warmth.

Easy to program and easy to use.

21 arpeggiator types.

13 effect types.

300 hand picked presets included.

11 skinable user interface.

Extensive MIDI support.

Harmonic Content Morphing (HCM) Synthesis is based on a large and expandable repertoire of standard waves like saw or pulse as well as complex waves like multi waves, trumpets, organs, pads, pianos, and voice samples. These waves can be modified in real-time by, for example, transposing the wave by one or two octaves and adding it to the original wave, altering its harmonic structure, syncing, compressing or expanding the frequency domain of the spectrum, making the wave fat using only one oscillator by transforming each wave into a hyper-wave, selecting some cycles of a sample and moving through them over time (comparable to wave-table synthesis). Any modification of a wave can be modulated producing lively shimmery sounds. In total there are more than 14,000 different spectra available for combination and modulation.

http://www.tone2.com/

Finger Bass

Finger Bass is a free software synthesizer developed by Lee Scott. Available format(s): stand alone application for Android.

Real time bass synthesizer.

The low pass filter self oscillates almost until blowing up.

https://vsts-leescott.rhcloud.com/

Fineline

Fineline is a free software synthesizer developed by kl.. Available format(s): VST, Audio Unit for macOS.

Fineline is a monophonic / polyphonic digital synthesizer.

Features:

2 Oscillators with waveforms sine-triangle-saw-square-pulse.

FM and sync.

External input and noise.

Fold algorithm.

1 ADSR volume envelope and 1 ADS filter envelope.

24dB lowpass filter or 12dB lowpass-highpass filter pair.

Filter overdrive.

2 modulation busses with 8 sources and 8 destinations each.

1 LFO with triangle, square and saw waves.

Arpeggiator.

Interface that allow you to edit parameters quickly and intuitively even if equipped only with a mouse. By selecting a couple of parameters you can change them via the edit knob with both speed and ease. You can also edit in standard click and drag parameter fashion.

http://c100.cascom.se/

Fernando

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

3 waveform oscillators with pitch, tuning, LFO, waveshaper, filter, plus ADSR envelopes.

Effects – Distortion, Flanger, Delay.

HP filter.

Arpeggiator.

Mod/pitch wheel and joystick controller.

http://www.sanusart.com/

Felix

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

Felix is inspired by the Octave Kitten hardware synth from the early eighties. The really powerful area of the Kitten was the modulation – the LFO / Sample+Hold routing to modulate the ADSR / VCO / VCF – it could produce many interesting effects and S&H sounds. Kriminal tried to capture this in Felix, as well as making it versatile in the normal spectrum of sounds.

Features:

1 VCO (saw/tri/pulse) plus white noise generator.

1 LFO – sine/square/S+H.

2 Sub Oscillators : square (-1 and -2 oct).

VCF – 4pole LP self oscillating filter.

VCA – ADSR.

200+ Presets.

http://homepage.ntlworld.com/lisa.millington/

Feldspar

Feldspar is a free software synthesizer developed by Contralogic Productions. Available format(s): VST for Windows 64b.

Feldspar is a virtual analog synthesizer featuring a range of tempo-based modulation options.

Features:

16 LFO waveforms.

Ring modulator with 18 algorithms.

Tempo-synced delay with high and low pass filters in the feedback path.

Drift function for controlling oscillator pitch instability.

Also included: FeldsparFX, a VST effect plug-in based on Feldspar’s architecture.

The download includes FeldsparFX – a VST effect plug-in based on Feldspar’s architecture.

http://www.contralogic.com/

Feeling

Feeling is a free software synthesizer developed by Dario Lupo / Daze. Available format(s): VST for Windows.

Feeling is a 3-oscillator Additive Synthesizer with a Saturator for each OSC, 2 Filters, 2 LFOs, Distortion, Double Chorus and 2 Delay effects.

http://www.dazesounds.com/

FEARkILLER X2

FEARkILLER X2 is a free software synthesizer developed by NOVAkILL. Available format(s): VST for Windows.

FEARkILLER X2 is a virtual analogue synth with FM and oscillator Hard Sync.

Main Features:

FM Oscillator with two waveforms and “Metal” setting.

Sub Oscillator with Hard Sync to main oscillator.

Low CPU unison.

State-Variable Vektor filter [12/24dB/octave].

6 Stage Modulation Envelope.

2 tempo-synced LFO, each with 7 waveforms.

Distortion and 32-step Gate effects.

7 row Modulation Matrix with 13 modulation sources and destinations.

http://www.novakill.com/

FDNCymbal

FDNCymbal is a free software synthesizer developed by Uhhyou. Available format(s): VST3 for Windows 64b, macOS, Linux.

Note: I don’t have mac so macOS build is not tested. If you find bug, please report it to https://github.com/ryukau/VSTPlugins.

Info: For Linux, LV2 version is available at https://github.com/ryukau/LV2Plugins.

FDNCymbal is another attempt to make cymbal sound. This one at least sounds like hitting a metal plate unlike WaveCymbal:

Stick oscillator. Just some impulses and sine waves.

FDN section makes stick sounds more plausible.

Schroeder allpass section adds metallic texture to the signal.

Tremolo can be used to simulate wobbling of cymbal.

JavaScript version is available. Requires browser that supports Web Worker and Web Audio. This is not exactly the same as plugin version, but using similar structure.

https://ryukau.github.io/FDNCymbal/

{See video at top of page}

https://ryukau.github.io/VSTPlugins/