The JustBoom Digi HAT is a high-resolution digital audio output board for the Raspberry Pi. It delivers an unmodified, bit-perfect digital audio stream via optical (TOSLINK) or coaxial (RCA) S/PDIF outputs, making it ideal for connecting your Pi to an external DAC, amplifier, or hi-fi system.

The board uses the I²S interface for audio input, reducing CPU load compared to USB audio solutions. It draws power directly from the GPIO header — no extra cables or power supplies needed. All GPIO pins remain accessible via an unpopulated 40-pin extension header for additional project customisation.

Key Features

• S/PDIF Output – Optical (TOSLINK) and coaxial (RCA) digital audio outputs
• Up to 192 kHz / 24-bit – High-resolution, low-jitter bit-perfect output
• Galvanic Isolation – Output transformer for electrical isolation from your hi-fi
• I²S Audio Input – Low CPU overhead compared to USB audio
• Plug and Play – No soldering required, mounting hardware included
• GPIO Passthrough – All 40 pins accessible via extension header
• IR Receiver Included – Optional infrared receiver in the package
• Software Volume Control – Adjustable from the Raspberry Pi

Specifications

• Audio Resolution – Up to 192 kHz / 24-bit
• Digital Outputs – Optical (TOSLINK) + Coaxial (RCA)
• Audio Interface – I²S via GPIO header
• Power – Supplied via Raspberry Pi GPIO header
• Compatibility – Raspberry Pi A+, B+, 2B, 3B

Software Compatibility

• Raspberry Pi OS, OSMC, Volumio, Moode, RuneAudio, Max2Play, PiCorePlayer, PiMusicBox, LibreELEC, and more

Ideal For

• Hi-fi audio streaming from a Raspberry Pi
• Digital audio output to external DACs and amplifiers
• Multi-room audio systems
• Media centre builds

Resources

• Getting Started Guide
• JustBoom Tutorials
• Software Guides
• Board Pinout Reference