Expansion board designed for 3 2 Model B B +The user can cooperate audio player system to set up their own network HIFI player after using HIFI DiGi+ boardThis is an expansion board designed for 2 model B & B+, adapt Wolfson company high-end digital chip. Using the 12S interface, support 16 to 24 audio data formats and the advanced shake reduction technology could control the Intrinsic period jitter in 50ps . Reductive degree is high, supporting hardware of controlling volume, and the user can cooperate audio player system to set up their own network HIFI player after using the expansion board. It's convenient that this expansion board also provide two output interface fiber (S/PDIF) and coaxial (RCA) for external device. User can the PC , boot off slowly, the supply noise and so on. It provides indicator light for you to observe the expansion board status easier. It also support in hardware volume control (I2C interface).It supply with supply, no external supply; and the use of -type filter supply design, effectively reduce the interference of the supply. PCB board with gold plating on the tall, curved traces (high-end HIFI DAC is using curved alignment). It is to better the continuity of the impedance signal to reduce signal reflections and refractions. When there is no network, it is easier to control playback. I2S interface are using direct digital output, reproduction and high non-USB interface DAC mode. Do not use other extensions GPIO.Notes: The product support runeaudio and osmc system,not volumio system when apply on 3 board . material: metalPacking List:1 x HIFI DiGi+ ModuleNote: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 +/- 1-3 cm.