This is a dedicated HIFI DAC expansion board (PiFi DAC+) designed for Raspberry Pi B+, using TI's higher-end DAC chip (PCM5122), using I2S interface, not USB interface, and can support hardware control volume ( The old DAC uses PCM5102A chip and cannot support hardware volume adjustment);After using this expansion board, the user can cooperate with the audio playback system (such as: volumio, etc.) to build their own network HIFI player; the expansion board provides two output interfaces for external power amplifiers and other equipment. With it, you can the problems of high PC power consumption, slow startup and shutdown, and loud power noiseThis PiFi DAC+ expansion board of B+ is based on the design of the old B DAC expansion board, upgraded with higher-end chips and circuits, and added more practical function expansion boards, higher performance, more trial Features, highly recommended color:BlueMaterial:PCBsize:6 x 5 x 1CMPackage Contents:1 x xI2S Interface1 x Sound CardOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.