Dual AD front panel

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Maddie MOD1

Dual AD

Envelope

Two independent attack-decay envelopes with per-trigger random timing variation.

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

Overview

Dual AD packs two independent attack-decay envelopes sharing the same attack and release knobs. The third knob dials in per-envelope random timing variation: fully CCW is rock-steady, fully CW adds a different random deviation to every trigger — stronger at short settings, lighter at long ones. Envelope 1 can also be fired by hand with the button. Outputs are fast 16-bit PWM.

Panel & I/O

Control Pin Function
POT1 A0 Attack time
POT2 A1 Release time
POT3 A2 Vary — random per-trigger timing variation
BTN D4 Trigger envelope 1
LED D3 Envelope 1 level
F1 D17 In — Trigger 1
F2 D9 Out — Envelope 1 (PWM CV)
F3 D10 In — Trigger 2
F4 D11 Out — Envelope 2 (PWM CV)

Features

  • Two fully independent AD envelopes from one 4 HP module
  • Per-trigger random timing variation for humanized, evolving dynamics
  • Manual trigger button on envelope 1
  • 16-bit PWM envelope outputs, 8-bit PWM LED

© 2026 Maddie Synths · firmware based on work by Rob Heel · original firmware CC0 1.0 · hardware design by Hagiwo