Butterfly front panel
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Maddie MOD1

Butterfly

Chaos · Modulation

A Lorenz-attractor chaos source for organic, non-repeating CV — chaotic, but never random.

Width
4 HP
Depth
28 mm
Power
+12V
MCU
Arduino Nano
Controls
3 pots · button · LED
I/O
4× 0–5V jacks

Overview

Butterfly runs a Lorenz attractor — the system that inspired the famous “butterfly effect” metaphor, where tiny changes lead to dramatically different outcomes. It produces organic, non-repeating CV movement that feels alive without ever being truly random.

The three knobs shape the attractor’s parameters, and the three CV outputs trace its X, Y, and Z axes. A trigger input resets the system, and a slow mode stretches the motion out for glacial modulation.

Panel & I/O

Control Pin Function
POT1 A0 Sigma — flow strength (x/y equalize + step size)
POT2 A1 Rho — divergence (calm → chaos)
POT3 A2 Beta — damping (z growth/decay)
BTN D4 Normal / slow mode
LED D3 Blinks at step rate
F1 A3/D17 In — Trigger (reset)
F2 D9 Out — X axis (PWM CV)
F3 D10 Out — Y axis (PWM CV)
F4 D11 Out — Z axis (PWM CV)

Features

  • Deterministic chaos — organic motion that never exactly repeats
  • Independent X / Y / Z CV outputs for three related-but-distinct modulations
  • Trigger reset to re-seed the system
  • Slow mode for ambient, drifting movement

© 2026 Maddie Synths · firmware based on work by Rob Scape · original firmware MIT · hardware design by Hagiwo