• ESP32-DevKitC : espressif
• Adafruit I2S 3W Class D Amplifier Breakout - MAX98357A : Adafruit
• Stereo Enclosed Speaker Set - 3W 4 Ohm : Adafruit
• AE-MICRO-SD-DIP Micro SD Card slot : Akizuki Denshi

• Arduino IDE
• arduino-esp32

Set SD card with "sound.wav" (44100Hz, 16bit, linear PCM). Only turn on the power.