Claves front panel

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Maddie MOD2

Claves

Percussion · Voice

A tunable claves/woodblock voice with morphable sine↔triangle waveform and 1V/oct tracking.

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

A simple, tunable claves/woodblock voice. The waveform morphs continuously between sine and triangle, the pitch tracks 1V/oct, and an exponential envelope with a cosine fade-out keeps the tail click-free. The LED follows the envelope on every hit.

Panel & I/O

Control Pin Function
POT1 A0 Decay time
POT2 A1 Waveform — sine ↔ triangle morph
POT3 / CV A2 Pitch (1V/oct)
IN1 GPIO7 In — Trigger
BUTTON GPIO6 Manual trigger
OUT GPIO1 Out — 10-bit PWM audio (~36.6 kHz)
LED GPIO5 Envelope follower

Features

  • Continuous sine↔triangle waveform morph
  • 1V/oct pitch tracking (~50 Hz – 1.5 kHz) with 16-sample averaging
  • Click-free exponential envelope
  • ~36.6 kHz, 10-bit PWM audio with linear interpolation

Patch ideas

Sound Decay Waveform Pitch
Classic claves 30% 80% (triangle) ~800 Hz
Woodblock 20% 90% ~1200 Hz
Melodic perc 50% 40% (sine) 1V/oct from seq
Deep tom 70% 20% (sine) 100–200 Hz
Rim shot 15% 100% ~1500 Hz

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