Synthesis

STriFE

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

STriFE is a synth that produces strange harmonics through ring modulation.

It only uses two oscillators, but each has its own filter (and envelope), and the second has several options for detuning and phasing.

It’s designed for chords and leads, but works nicely for bass sounds as well.

Features:

23 waveforms to select from.

One filter per oscillator.

Separate envelopes for each oscillator’s filter.

http://anosci.net/vsts.html

Stoq

Stoq is a free drum machine VST plugin developed by xoxos. Compatible OS(s): Windows.

Stoq is a physical model for synthesizing continuous shaker and rattle timbres. The signal path, inspired by Perry Cook’s PhiSEM synthesis, routes a stochastically generated impulse series to five resonant bandpass filters running in parallel. The envelope and LFO are assigned to multiple destinations to animate patches.

Four key-groups are provided for creating performance articulations. The approximate pitch of the signal can also be set to follow the keyboard for tuned synthesis.

Presets include tambourine, brushed snare, jingle bells, and non-instrumental sounds like footsteps and chewing.

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

Stigma

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

The Stigma is a software instrument for Microsoft Windows (VST) and macOS (VST/AU) simulating the KORG Sigma KP-30 Performing Synthesizer from 1979. It is written in native C++ code for high performance and low CPU consumption. Main features are:

Nineteen Presets with individual filters, envelopes, and amplifiers.

Two band-limited oscillators with 4 footages (32′ to 4′).

Synthe preset section:

Eight presets including Noise and Ring modulator.

Individual lowpass and global highpass filters.

Instrument preset section:

Eleven presets, Delayed Vibrato effect.

Effect section:

Portamento, Quarter Tone, Keyboard Sensor (aftertouch) and more.

Tweaks (not to be found in the original Sigma):

Up to 64 voices polyphony with Velocity.

Chorus/Ensemble section.

Preset editor.

All parameters can be controlled by MIDI CC.

40 additional presets by kraftraum.

Double precision audio processing.

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

https://SoundCloud.com/full-bucket/stigma

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

Steam

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

Steam is a “Fizmo-alike” wavetable synth with two ‘scannable’ table-based oscillators and two multi-mode filters that include a variety of sideband modes to take advantage of evolving timbres. It is optimized for dense shifting, motile, ‘organic’/noisy, chaotic textures.

Steam is available as a VSTi for Windows in two versions – the free version is monophonic, the full version costs US$20 and allows 6 voices of polyphony.

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

Star Cym

Star Cym is a free drum machine VST plugin developed by xoxos. Compatible OS(s): Windows.

Star Cym features cymbal synthesis using parametric delay network.

The arrangement of delays provides useful variance.

This VST was released years ago as part of a bundle. In retrospect, it sort of sounds like acoustic cymbals that don’t move.

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

SQ8L / SQ8X

SQ8L / SQ8X is a free software synthesizer developed by Siegfried Kullmann. Available format(s): VST for Windows.

SQ8L is a software model of Ensoniq’s classic 1980s synth SQ80. The SQ80 features 3 digital wavetable oscillators for each of its 8 voices which are fed through analog 4-pole lowpass filters (-24dB gain) with resonance. Sound parameters can be modulated by 4 envelopes, 3 LFOs and several MIDI sources. The SQ80 also has a predecessor, the ESQ1, which can do most of the same stuff.

Although the technology may seem obsolete, these synths can produce a wide variety of interesting and extremely usable sounds. Thanks to the lo-fi oscillators and the analog components it can sound very digital and dirty, but also very analog and warm. Which is a good thing because modern synths often tend to sound rather clean.

The SQ8L (“L” stands for “Light”) is the free demo version of the forthcoming SQ8X (“X” for “eXtended”). Besides any bugs that will be fixed in the full version and planned features that won’t find their way into the light version, there are only a few limitations:

Polyphony limited to 8 voices.

Program change messages ignored.

Common MIDI controllers (Master Volume, Pan,…) by default have no effect and must be programmed as modulators.

When used with a sequencer, the only sound the host can save within the song file is the one in the edit buffer. The full version will store the entire library (which makes sense when program change messages are used).

LFO humanization not implemented.

No Split/Layer to combine several sounds.

No internal sequencer (and there will never be one).

The full version SQ8X will have the following additional features:

Combinations of up to 4 single sounds.

Adjustable polyphony (far more than 8 voices).

New Filter algorithms with different modes (lowpass, bandpass, highpass).

2nd Filter and different routing modes for the filters: serial, parallel, split.

Improved GUI.

http://www.buchty.net/ensoniq/

Sprike

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

Sprike is an extended variant of Tunefish4, the virtual analog synth originally created by Brain Control.

We made Sprike cooperate more nicely in a MIDI-controlled environment (MIDI sequencers). Following MIDI standards, it responds to bank and program selection messages, master volume and pan controllers. Presets are stored in compliance with operating system conventions. We also added four new MOD sources and enhanced it with an on-screen keyboard. The user interface was enhanced with master volume/pan controls and a level meter. Delay times can be set in terms of note lengths.

Sprike is very lightweight, so you can add 10 or more instances to your project without much impact on CPU load. It has the same expressive and crisp sound as Tunefish and comes with a new bank of factory presets.

Sprike is free open source software. You will find its source code on GitHub.

http://www.cognitone.com

Spook Organ

Spook Organ is a free software synthesizer developed by JC. Available format(s): VST for Windows.

Features:

Two banks each of seven oscillators.

Each bank can be set to use a different waveform. (Sine, Saw, Ramp, Triangle, Pulse, White Noise & Pink Noise) This makes it possible to additively create some very organ like, or very grungy sounds, especially when combined with the modulation section, which is basically a chorus.

http://clift.xs4all.nl/codex/terra/html/index.php

Spicy Guitar

Spicy Guitar is a free software synthesizer developed by Keolab. Available format(s): VST, Audio Unit for Windows 64b, macOS.

Spicy Guitar is an innovative acoustic guitar simulation software. Relying on a brand new technology, Spicy Guitar lets you generate realistic guitar parts as well as original string-based sounds.

Overview:

The character of 9 real guitars has been captured and a wide range of guitarist’s playing techniques, from vibrato to palm muting. Because it is based on a full physical modeling of the guitar, the characteristics of the instruments – such as the body size or the strings’ material – can be changed in real-time. It offers to the user a lot of sound possibilities.

Spicy Guitar has a chords detection system that converts piano chords into guitar chords and automatically strums them, which makes the creation of complex rhythms easy.

http://www.spicyguitar.com/

SpatSynth 8

SpatSynth 8 is a free software synthesizer developed by Acousmodules. Available format(s): VST for Windows.

Subtractive synth:

2 oscillators

1 multimode resonant filter

3 LFOs

2 envelopes

Frequency modulation and synchro between the two oscillators

8 modulated outputs with gestual control of the most important parameters associated with spatial movements.

10 notes polyphony.

http://acousmodules.free.fr/