Wolfson Raspberry Pi Audio Card 3.5 mm jack stereo line input for connection to external devices such as digital audio players (e.g ipod) or mobile phones 3.5 mm jack stereo line output for connection to devices such as external stereo amplifiers or powered speakers Phono jacks for S/PDIF digital stereo audio input and output 2x on-board high quality MEMS microphone for audio capture and a seperate 3.5mm jack for microphone input On board low power very high efficiency class D power and amplifier