01 กุมภาพันธ์ 2559
ผู้ชม 1799 ผู้ชม
Developed to be simple to set up and use, the Rega DAC-R is designed
to optimise performance from any two channel PCM digital audio source.
With the PC now widely accepted as a credible medium for storing and
streaming music,the use of high quality lossless files such as WAV, FLAC
and ALAC offer performance through the DAC-R equal to, and in some
cases better than, Red Book CD. Great care has been taken to remove
noise generated by the PC and other input sources. (During development
this was identified as a major drawback with many DAC’s on the market
today).
The DAC-R is housed in a custom aluminium and steel case and boasts
a pair of Wolfson DAC IC’s, three user selectable digital filters and one
isolated asynchronous USB, two isolated Co-axial inputs & two Toslink
SPDIF inputs.
The DAC-R has been designed and engineered to integrate perfectly into
any system and achieve the highest performance in its class. We hope
you enjoy this Rega product for many years to come.
The optical and coaxial input stage comprises a Wolfson digital receiver
with a high stability, low jitter clock driving the receiver PLL. The receiver
and PLL have their own dedicated power supplies.
The DAC stage comprises a pair of parallel-connected Wolfson WM8742 DAC’s,
that are driven via a buffer stage, which ensures the integrity of the data being fed
to the DAC IC’s similar to the arrangement used in the Isis reference CDP.
The USB input stage is comprised of a bit perfect XMOS USB Audio 2.0
with asynchronous clocking. The USB input stage feeds the Optical and
Coaxial input stage via an isolating transformer giving total isolation from
the host computer.
The output amplifier employs a discrete differential, multiple feedback
filter and output amplifier, with a high cut-off frequency for use with higher
sample rates. We decided not to use a sample rate converter and process
the data at the incoming sample rate which keeps the signal processing to
a minimum. Jitter was minimised by synchronously clocking the digital data
with our receiver PLL (removing any jitter from the input signal).
All the capacitors associated with the analogue signal path are audio grade
bypassed with MMK polyester capacitors, and low impedance conductive
polymer capacitors are used for DAC decoupling. The power supply
utilizes a toroidal transformer, fast rectifier diodes and again audio grade
capacitors. There is a power supply for the control micro controller, separate
from the digital & analogue audio stages. Special attention being paid
to the inter IC control signals ensures the control data noise is kept to a
minimum.
DAC 2x Wolfson WM8742
Frequency Response (100KΩ load) Filter 1 selected
Low data rate 44.1/48kHz = 10Hz -0.05dB to (44.1K) 20.02kHz (48K) 21.7kHz -0.03dB
Medium data rate 88.2/96kHz = 10Hz -0.05dB to (88.1K) 28.7kHz (96K) 31.2kHz -3dB
High data rate 176.4/192kHz = 10Hz -0.05dB to (176.4K) 44.1kHz (192K) 47.7kHz -3dB
Maximum output level = 2.175V into 100KΩ load
Bit resolution (all inputs) 16 to 24bit
Supported data rates = 32, 44.1, 48, 88.2, 96, 176.4, 192kHz
Total Harmonic Distortion all inputs (24bit 96kHz) = 0.006% @ 1kHz
Signal to Noise Ratio -105dB (relative to maximum output level with a 100Hz to 22kHz bandwidth)
Digital inputs
USB Asynchronous Isolated (24bit 44.1/48/88.2/96/176.4/192kHz)
Input 1 Optical/Toslink (24bit 32/44.1/48/88.2/96/176.4/192kHz)
Input 2 Optical /Toslink (24bit 32/44.1/48/88.2/96/176.4/192kHz)
Input 3 Isolated 75Ω Co-axial (24bit 32/44.1/48/88.2/96/176.4/192kHz)
Input 4 Isolated 75Ω Co-axial (24bit32/44.1/48/88.2/96/176.4/192kHz)
Digital SPDIF outputs (via receiver & PLL)
Optical/Toslink
Isolated 75Ω Co-axial
Power 230v/115v/7.6W
Dimensions W 215mm x D 320mm x H 80mm
Remote NEC system (6E91)
Weight 4.0 Kg