Full Bucket Music has released Stigma – a free virtual instrument which emulates the Korg Sigma KP-30 Performing Synthesizer. The vintage synth was made in 1979, and although it’s not one of the most renowned products from Korg, it’s a lot interesting so that the user can have the chance to have an idea of how it was to play a synth like that.

Sigma has two oscillators: the first one is called “Synthe”, and it contains eight presets made up mostly by waveforms. Upon each preset, there’s an additional knob, which will control the main parameter of the sound (for example Attack/Release, Decay, Clock). The user can activate from one to all presets at a time.

The second oscillator is called “Instrument”, and it has 11 presets that can be activated individually or simultaneously. Each preset also has an additional knob that controls the main parameter of each preset (for example, cutoff frequency, pulse width, tone, attack, decay).

Sigma also comes with an Effect section which instead of having typical reverb, delay, phaser, and other known effects, will have more basic parameters, such as octave up and down, portamento, key hold, vibrato, and more.

The instrument has a Control section, with knobs for volume, balance and pan. There’s also a Modulation section, where it’s possible to set destinations to sources like vibrato, noise, LPF cutoff and HPF cutoff.

There are new features in Sigma, that wasn’t from the original synth. The virtual instrument comes with the possibility to set up to 64 voices of polyphony, in the Magic section. It comes with 40 additional presets and it’s possible to save custom presets as well. A midi learn button, when activated, will allow controlling every parameter of Sigma using a midi controller.

Another cool feature is a built-in Chorus effect, with independent settings for Synthe and Instrument.

Sigma has a hidden Preset Editor section – just click on the warning message below the Sound Manager section, and then some new knobs will appear. There are controls for Gain, Cutoff, Resonance, Env Mod, and more, as well as ADSR knobs.

Stigma is available for free in 32 and 64-bit VST format (Windows).

Visit Full Bucket Music website and download Sigma for free.