Coda-88

Minimal piano sound module/expander with dynamics based on Arduino and WAV Trigger

© 2018 Sandro L'Abbate

Features

• 88-key keyboard compatible
• MIDI connection
• Zero boot time
• Low latency
• Polyphony (14-stereo)
• Realistic dynamics (3 sampling layers)
• Dumper and release-key effects

Parts

• Arduino UNO
• WAV Trigger
• 6N138
• Diode 1N914
• Resistor 220 Ohm (x2)
• Resistor 4.7K
• Switch (optional - you need to disconnect RX before upload)

Schema

WAV Trigger SVG from sjpiper145

Arduino

1) Libraries

• AltSoftSerial
• Metro
• MIDI
• wavTrigger

2) Dumper pedal and release-key sounds

Set true these two variables (leave false for a better performance):

bool RELSOUND = true;
bool PEDALSOUND = true;

3) Upload

Disconnect (or use switch button) RX connection from MIDI to Arduino before upload

4) Boot/reset

Press reset button on the Arduino after every boot (or strange behavior)

WAV Trigger

Samples numeration (ex. 032.wav)

Samples	Start	End
Init sound	020
Piano	021	108
Medio	109	196
Forte	197	284
Release keys	285	372
Pedal down	373
Pedal up	374

Piano Samples

Download this folder and copy its content into the WAV Trigger microSD.

These sample kit comes from Iowa Piano (main piano) and Salamander Piano (only for dumper and release sounds). Both libraries are free licensed.

See here for the best microSD cards for audio.

Official Library

https://github.com/robertsonics/WAV-Trigger-Arduino-Serial-Library

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Video demonstration

Coffee?