Crunch-E is a keychain form factor music-making platform that is both limited and limitless. The current software supports 4 tracks, 10 synth instruments, and 2 drum machine banks, but who knows where developers will take the open-source software next?

Crunch-E hardware comes in a few flavors. You can build it yourself on the cheap or use the schematic to design your own PCB.

Crunch-E hardware consists of an ESP32 microprocessor, a MAX98357A I2S sound amplifier, 4 LEDs, and an LM1117 power regulator. It can be obtained in a fully manufactured and very sleek form, or it can be built out of development and breakout boards (ESP32 dev boards, MAX98357 breakout boards, and Arduino keypads can all be purchased on AliExpress or Amazon for a reasonable price).

DIY Build Parts:

• ESP32 Dev Board
• Max98357 Breakout Board
• Arduino Compatible Keypad
• 4 LEDs + Required Resistors