4. Buttons and ports, Operating modes, Signal input, output method and Gain description for R9

[Buttons and Ports Labeled]

What is the function of the ground switch on the rear panel?

It is used to switch the ground connection of the PCB and outer shell. When switching to GND, the PCB is connected to the outer shell. When switching to NC, the PCB and outer shell are disconnected. This is mainly used to optimize the connection between the two devices of the common ground loop interference.

[Sigal input supported by R9]

R9 supports HDMI input, USB input, optical input, coaxial input, Bluetooth receiving, Ethernet, TF card and other signal inputs to meet your multiple use conditions.

[Output supported by R9]

R9 supports XLR4 headphone out, 4.4mm balanced headphone/line out,6.35mm headphone/line out;

Back panel supports and RCA line-out, Optical out,Coaxial out, XLR3 line out.


There are 5 levels,Ultra High modes, Super High and High, Medium Low gain, corresponding to 5 levels of output voltages(0dB,-3dB,-9dB,-15dB,-21dB).

You can select different gains according to the earphones used.


[Settings of Analog Output Level]

The R9 supports 4 output levels. Different level position means different output modes. Here are details

(√ means the current level has output while × means no output).