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GREAT CONJUNCTION >> Generative FM Sequencer/Synth

GREAT CONJUNCTION >> Generative FM Sequencer/Synth

Regular price $350.00 USD
Regular price Sale price $350.00 USD
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GREAT CONJUNCTION is a generative sequencer and synthesizer that utilizes a vintage Yamaha YM2413 FM sound chip for onboard sound reproduction.


It creates melodic, chaotic, rhythmic, glitchy, soothing, hypnotic, curiously evolving atmospheres and polyrhythmic puzzles.

General Features include:

  • 3 independent, 1-32 step generative sequencers
  • random, euclidean & cellular automata algorithms for event distribution
  • 8 parameters per sequencer (with additional sub-parameters)
  • variable evolution, per parameter, per sequencer
  • independent sub-division for each sequencer
  • monophonic or 3-note chord modes for each sequencer
  • free running or MIDI re-trigger modes for each sequencer
  • external key mode with 9 note polyphony
  • full control over YM2413 FM synth parameters
  • 100 presets synth sounds
  • 10 save slots
  • full MIDI implementation for sequencer & synth parameters
  • independent MIDI In/Out for each sequencer
  • 12 knobs, 5 buttons
  • 20x4 backlit LCD display
  • Send or receive MIDI clock on USB or TRS-A
  • 3D printed, semi-transparent enclosure

GREAT CONJUNCTION is NOT a deliberate instrument.

You cannot intentionally place notes or events in a sequence.

Instead, sequences are generated algorithmically using one of three methods (pseudo-random, euclidean or cellular automata).

Sequencer events trigger the internal YM2413 FM sound chip, and can trigger MIDI output.

The Yamaha YM2413 chip is only capable of producing one custom sound. The three sequencers can send conflicting data to the YM2413, causing it to manifest tones that would be difficult or impossible to program directly.


Sequencer parameters include:

  • INSTRUMENT (choose from 100 presets, or edit your own sound)
  • STEP (1-32 steps per sequence)
  • EVENTS (the density of events - based on the algorithm)
  • TYPE (the algorithm used to create the sequence - pseudo-random, euclidean or cellular automata)
  • ROOT NOTE (the base pitch from which pitches can be derived)
  • OCTAVE (the base octave from which pitches can be derived)
  • SPAN (the octave span above the base octave in which pitches can be randomized)
  • SCALE (43 scales)

All parameters can be periodically and individually evolved over time.

Most parameters have an additional sub function (detailed in the manual).

FM synth parameters include:

  • Modulator & Carrier ADSR envelope
  • Modulator & Carrier envelope rate
  • Modulator & Carrier envelope mode
  • Modulator & Carrier waveform (sine & half sine)
  • Modulator & Carrier key scale level
  • Modulator & Carrier frequency multiplier
  • Modulator & Carrier vibrato and tremolo
  • Modulator level
  • Feedback level

What it is NOT

  • GREAT CONJUNCTION does not playback or comprehend video game music files
  • GREAT CONJUNCTION does not currently incorporate the 16 ROM instruments or 5 ROM drum voices of the YM2413


  • micro USB Cable
  • printed manual
  • rubber feet
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