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.
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.
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.
Push the button "Gain", the display will show between "
L, H" .
"L" mean the unit
working on low gain (100 steps and 7DB).
"H" mean the unit
working on high gain (100 steps and 17DB).
applied the new gain technology ,no
any switches,relays or parameter of the amp change while change the gain
modes so the sound quality is exact same in different gain modes.
Users just want to choice the better mode for easy adjust the volume
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, in this
mode, the display show "d" instead "P" and the volume number show
"--" ,the volume can not adjust anymore (The headphone
output mode has not effect).
into , XLR / RCA /ACSS output as preamp .
Headphone output mode has not any effect by this selector .
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
Push into 4 pcs jumper for got the warmer sound flavor. It is effect for
Setting Function Introduce (It has effect on digital inputs only):
The DAC can setting the digital
process functions on front plate to change the sound flavors, without open the unit .
How to active the
digital setting mode:
The "DAC/HP" and "Input"
buttons has dual functions.
While the input between input 5
and input 6, the "DAC/HP" button can select the output mode between
"H" (Headphone output) and "P" (Preamp output) .
While the input is between 1 to
4, the "DAC/HP" button become dual functions.
In case, push the "DAC/HP"
button one time, the left first display flashing around 3 seconds,
in term if the "DAC/HP" button has not push again, the output mode
change either "H" or "P".
If the "DAC/HP" button push
again while the left first display flashing, the unit go into the
digital setting mode.
Before push the
we are advice user turn low the amp volume, stop the
music track playing .
the aim to reproduce the best sound quality, the DAC without mute design , change the
setting may output circuit switch sound .
Around 5 seconds after non
any button had push, the display stop blink, user
can click the music track to playing and turn up the volume.
DAC/HP button :
unit had went into the digital setting mode, the one digit display
will blink for active the function setting , push the "Input" button
can change function .
While the display blink, push "DAC/HP"
again , the right next one digit display will blink for setting .
Left 1st display : Oversampling
"O" for select oversampling,
"N" for select NOS mode.
Left 2nd display : OS and NOS modes
setting on "O" mean the DAC working under oversampling
mode, lower number OS modes sound became warmer
and smoother. Or depend on your sense .
Mode "0" : class
technology NOS mode.
Mode "2" : 2X oversampling.
Mode "4" : 4X oversampling .
Mode "8" : 8X oversampling.
While OS setting on "N"
mean the DAC working under NOS mode,
different modes offer different sound features, usually mode 3 is
most users favorite. Or depend on your sense .
Mode 1 : Simplest data process
Mode 2 : Data fifo.
Mode 3 : Fastest data process.
Left 3rd display : PLL
(1) or Disable (0) PLL for USB and HDMI inputs, we are advice setting
Active (1) for the low performance source but Disable (0) for the
high performance source, or depend on yourself sense .
Left 4th. display : Synchronizer
If the HDMI
input had noise, distortion or some samplings no sound, user can setting the synchronizer ON
(1) or OFF (0) to fixed the issue. In default is OFF (0) .
Left 5th. display : Display
Active (1) the display
auto dark, the display will become dark in around 10 seconds after
stop operate any buttons . Disable (0) the display auto dark, the display light
the display non blink, for select the input sources.
While the display blink, for
setting the digital process functions.