Full Bucket Music: Stigma ς
A free software synth clone of the KORG Sigma.
German programmer and software engineer Björn Arlt began building VST plugins under the name Full Bucket Effects in 2010. Being a musician, and a synth enthusiast from a young age, he was drawn to analysing and building software synths. He now offers both synth emulations and effects as freeware through his website.
The Stigma is a software instrument simulating the KORG Sigma KP-30 Performing Synthesizer from 1979. The Instrument section contains 11 presets that can be individually activated by their associated ‘rocker’ switches. Each preset has one additional knob that controls one main parameter of the sound. The sources for all Instrument presets are the respective footages of VCO 1.
The Synthe section contains eight presets that can be individually activated by their associated Rocker switches. Each preset has one additional knob that controls one main parameter of the sound. The sources for all Synthe presets are the respective footages of VCO 2.
There is also an additional Ring Modulator switch that replaces the standard output of the Synthe section with the Ring-modulated signal of the Synthe and the Instrument sections. Note that in order to hear any sound when Ring Mod is on, at least one preset of both sections has to be activated. Along with the Ring Mod switch comes a control for tuning/detuning the VCO 2 by ± 7 notes. This pitch control will only be active when Ring Mod is activated, too.
Replacing the joysticks are four modulation paths: Vibrato (Joystick 1 Y axis up; controls the Vibrato modulation depth), Noise (Joystick 1 Y axis down; controls the Noise modulation depth), LPF fc (Joystick 2 X axis; controls the cutoff of the Synthe lowpass filters), and finally HPF fc (Joystick 2 Y axis; controls the cutoff of the Synthe highpass filter). For each modulation path the modulation source can be selected from one of the 120 MIDI channel controllers, the output of the Vibrato LFO, the PWM LFO, the S/H LFO, Pitch Bend, or Channel Pressure (Aftertouch). Finally, Velocity is also available as a source for LPF fc.
Synthe Preset Section:
Eight presets including Noise and Ring modulator
Individual lowpass and global high-pass filters
Instrument Preset Section:
Eleven presets, Delayed Vibrato effect
Portamento, Quarter Tone, Keyboard Sensor (aftertouch) and more
Tweaks (not found in the original Sigma):
Up to 64 voices polyphony with Velocity
Nineteen Presets with individual filters, envelopes, and amplifiers
Two band-limited oscillators with four footages (32′ to 4′)
Supports MTS-ESP by ODDSound dynamic micro-tuning
Resizable user interface (not N version)
MIDI Learn – all parameters can be controlled by MIDI CC
40 additional presets by kraftraum
Plugin supports Windows and macOS (32 bit and 64 bit)