Built In 4 Groups of  DA-8 R-2R Modules
Built In FPGA Processor to Reject Jitter 
DSD , DXD 32bit / 384K Support From USB / HDMI
Built in real balanced headphone amp.
Built with OCC and Hi-end parts

Please not:
          The R-28 had built in fully dedicated discrete R-2R resistor ladders DA modules. Based on some users feedback from Audio-gd other's R-2R products, it need longer burn in time to achieve the best sound quality and performance.
          Even it had burn in over 100 hours before shipping , but we are advice customers burn in it more than another 500 hours.
          You can power on it with playing music but shut down the volume for quickly finished burn in if you are at home.
          The mini remote shipped without battery because the either DHL and EMS limit shipping by plane , customers want to buy one CR2025 battery and assemble in the remote.



Input mode: 
Push the button "Input" for select the input sources .
Input 1: HDMI-IIS input.
Input 2: USB input.
Input 3: Optical input.
Input 4: RCA - coaxial input.
Input 5: RCA analog input.
Input 6: XLR analog input.

Gain mode: 
Push the button "Gain", the display will show between " L, H, F" .

"L" mean the unit working on low gain (100 steps and 7DB).

"H" mean the unit working on high gain (100 steps and 17DB).
"F" mean the volume change faster (64 steps) , working on high gain (17DB) .

Output mode: 
Push the button "DAC/HP", the display will show between " P , H".

"P" mean the unit output from XLR / RCA / ACSS from rear. XLR and RCA can connect to two amps in same time.

"H" mean the unit output for headphones on front plate.

The DAC/PREAMP output mode selector : 
Pull out , XLR / RCA /ACSS output as decent DAC. Push into , XLR / RCA /ACSS output as preamp .
Headphone output modes have not any effect by this selector .

The display auto dark : 
Push into the jumper is auto dark .Please operate the jumper while the unit power off .


Warmer sound setting : 
The unit had built in a lot setting in the FPGa for users select the best suite sound flavors but they only effect the digital input.
  Push into 4 pcs jumper for got the warmer sound flavor. It is effect for all inputs.

Jumpers setting


　

S1 without jumper (Working on overampling mode)

Jumpers Number

Jumper Setting

Functions describing

S3

Inactive (OFF)

Active (ON)

PLL setting

S2

Note 2

 8X OS

2X OS

The sound will become smoother and warmer while setting lower oversampling.Default setting in the 8X OS which is the best neutral sound.

S6

 (OFF)

 (ON)

S4

Reserved

S5

Reserved

S1 with jumper push into (Working on NOS mode)

Jumpers Number

Jumper Setting

Functions describing

S3

Inactive (OFF)

Active (ON)

PLL setting

S2

Note 2

S7

Reserved

S6

S4

 (ON)

S5

 (ON)