Full Bucket Music: FB-3100

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 FB-3100 is a software synthesizer plugin that emulates the classic KORG PS-3100 Polyphonic analog synthesizer from 1977. Its Signal Generators offer six selectable waveforms (Triangle, Sawtooth, Square, Rectangle, Pulse, and Pulse Width Modulation), four octave ranges (16′ to 2′), fine and coarse tuning, and frequency modulation controls. Note that per key (C to B), only one top-octave oscillator exists — the lower octaves are generated by frequency division. This means that the signals of the same key at different octaves are always in phase, and can be verified by analysing the output of the FB3100 with an oscilloscope.

The output of the Signal Generators is fed into a two-pole lowpass filter section with adjustable resonance (Peak). As this is an emulation of the K-35 filter found in the PS-3100 it cannot be pushed to self-oscillation. The envelopes are the standard ADSR type, however the release time cannot be controlled continuously. Instead this can be switched in three steps: Damp (very short), Half Damp (pretty short) and Release (pretty long).

The individual voice signals are mixed into a single monophonic signal (the direct signal), and sent into the Resonators section. This is a parallel arrangement of three bandpass filters with high Q (i.e. resonators) and individually adjustable centre frequencies. The Intensity control determines the mix between original and effect signal.

Tweaks – Features not found in the original PS-3100 hardware synthesizer: 

• Additional modulation sources ‘MG1’, ‘Key’, ‘PB’, ‘PB+’, ‘VC1’ to ‘VC4’
• Additional S/H input sources ‘Rnd’, ‘Key’, ‘PB’, ‘PB+’, ‘VC1’ to ‘VC4’
• Additional trigger sources ‘Clk1’, ‘Clk2’, ‘Trg’, ‘Trg2’
• Panorama control for Final and Direct output

Features:

• Close emulation of behaviour and all controls of the original hardware
• Band-limited oscillators, classic two-pole lowpass filters
• Resonators section
• Two Modulation Generators, Sample & Hold
• Additional paraphonic Envelope Generator
• Semi-modular patch panel
• Micro-tuning option
• Additional tweaks
• MIDI Learn – all parameters can be controlled by MIDI CC
• Plugin supports Windows and macOS (32 bit and 64 bit)