🎛️ MOD303 panel art
coming soon

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Maddie MOD2

MOD303

Bass · Sequencer

An 'acid' 303-ish bass voice with a built-in Turing-style generative sequencer.

Width
4 HP
Depth
28 mm
Power
+12V / −12V / +5V
MCU
Seeed XIAO RP2350
Controls
3 pots · button · LED
I/O
2 gate in · 1 CV in · PWM audio out

Overview

“ACIDWALK303” is a 303-style bass voice with a generative sequencer baked in. POT1 crossfades from a locked 8-step pattern, through total randomness, to a locked 16-step pattern — a Turing-machine-style probability control. Clock it externally and it walks, mutates, and accents on its own.

Panel & I/O

Control Pin Function
POT1 A0 Turing — randomness + length (8-step ↔ random ↔ 16-step)
POT2 A1 Decay — amp decay + bite (accent extends it)
POT3 / CV A2 Transpose — quantized semitones
IN1 GPIO7 In — Clock (rising edge advances)
IN2 GPIO0 In — Accent hold
BUTTON GPIO6 Short = scale · double = waveform · long = regenerate
OUT GPIO1 Out — PWM audio
LED GPIO5 Step / accent / slide blink

Features

  • 303-flavoured bass voice with slides and accents
  • Built-in Turing-style generative sequencer
  • Locked 8/16-step or fully evolving patterns
  • Quantized transpose, switchable scale and waveform

© 2026 Maddie Synths · firmware based on work by the HAGIWO MOD2 community · original firmware Open source · hardware design by Hagiwo